This is a very long post about Apple IDs. I wrote it as a summary for me, so I could remember what I did and why, and if I need to re-do things, I can come back here.
I started with one Apple ID (so I thought) for all my devices and all Anne's devices. We were sharing. It reached the point where it was too difficult to continue. Over a six-week period, I separated my devices and Anne's devices, and got to a point where we are getting full benefits from our Apple devices and we are both happy.
I had a couple of small failures and these cannot be resolved.
This is how it all happened.
Back in March 2005, I created an account with Apple, using my home email address. It was just an account so I could buy a Mac Mini. In May 2007, I bought an iPod and registered it with Apple using that same email address. By this time, the iTunes store was open and my email address was used to buy music. I think about this time, that email address became an Apple ID and was my key to my Apple account. I don't think it was called an Apple ID at this point.
In July 2009, I signed up for a MobileMe account, $99 for a year of MobileMe with 2G storage. This gave me a new email address, a me.com address. So now I had two different email addresses registered with Apple. I think I had two different accounts by this time. One was H@myhome.com and the other was HA@me.com. Next year, Apple was calling these email addresses Apple IDs. I guess by this time I had two. I didn't use the me.com address much. I used the other one mostly for app and music purchases.
I kept my me.com subscription going till 2011. Somewhere in there, we bought a Mac Mini for Anne and set it up with her own Apple ID and that was a me.com address too. Call this one AA@me.com. So now we have got three email addresses and three Apple IDs in play.
In June 2011, Apple announced iCloud. Both our me.com addresses acquired equivalent icloud.com addresses. And we didn't have to pay $99 a year for them. And then I kind of just forgot about the me.com and icloud.com addresses. We didn't use them for anything. And now we have five email addresses and three Apple IDs in play.
I bought a used iPad 2 and used the H@myhome.com email address for the Apple ID. Once Anne got her first taste of an iPad on a trip back to Australia, she did not want to let it go. I ended up buying one for her there and leaving it with her in Australia when I came back. But so I didn't have to pay for apps twice, I used my Apple ID in Anne's iPad. This is where things started to go wrong.
The years went by and we replaced our Mac Minis, and used my H@myhome.com Apple ID on all of them. I got an iPhone and newer iPads, and used the H@myhome.com Apple ID on them. Anne got a newer iPad and then an iPhone, and I continued to use the H@myhome.com Apple ID for everything.
I forgot about all the other addresses and Apple IDs.
When Anne got an iPhone, I had to do some differentiation so she could get messages and Facetime and we could keep ours apart. It was kind of possible to do something about merging Apple IDs back then. I remembered Anne's email addresses - AA@me.com and AA@icloud.com - and somehow added them to my Apple ID. Her Apple ID got subsumed into mine, and her two email addresses became aliases for my Apple ID email address. That let us keep the messages and Facetime separate. I'm still not sure what that was all about, but it worked, but it was just one more step down the wrong path.
Skip forward to 2018 and I have a bunch of devices with my Apple ID, and Anne has a bunch of devices with my Apple ID and we are sharing everything and it's really ugly. I was using ownCloud for calendar and contacts, and Anne was using a different ownCloud for calendar and contacts and it all just wasn't working well. We weren't using iCloud for anything, not backups, not syncing, it was all just too ugly.
We ended up with five email addresses, and two Apple IDs, but we were only using one Apple ID and two of the email addresses.
By 2018, it was all too hard and it was time to break us apart. Apple had Family Sharing by now, and it looked like it worked really well. I did a lot of reading to work out the best strategy. I had a lot of experimentation to do.
Anne went back to Australia for a month so I got a chance to experiment.
First, I created a new Apple ID for Anne. Call this one AB@icloud.com. I took her old iPad Mini and switched it to the new Apple ID. None of the apps or data was deleted. That was my first worry, but it worked just fine.
Back to my devices. We were going to be using iCloud a lot, and the free 5G iCloud space we had each was not going to be enough. I signed up for the 200G storage space at $4 a month. I went for the 200G size because it can be used for Family Sharing.
I turned on Family Sharing, and invited Anne's new Apple ID to join, and then accepted the invitation on her old iPad. So far, so good. I then turned on a whole bunch of services on my iPhone and iPad and MacMini and MacBooks, and got them to sync to iCloud and backup to iCloud. That all worked nicely, did not bleed across to Anne's old iPad. It worked very nicely. Sure blew past the 5G storage limit. I went to about 10G. This was nice. All my photos on my iPhone were automatically sent to my iPad and MacMini. Same with the iBook documents. Now I understand more about iBook storage. When I recently upgraded to a new iPad, if I was doing all this iCloud syncing stuff, I would not have lost any documents. Now I know better.
Some of the iPhone settings must have applied to Anne's iPhone too. Every new photo she took in Australia would appear on my devices back here. I left them alone, did not want to delete anything.
Once all my devices were stable and working and syncing nicely, I went back to Anne's old iPad. I started syncing to iCloud on her new Apple ID. All went well. So I did it to her Mac Mini. Holy hell. Anne does a lot of creation stuff. She will create projects and scan things and make PDFs and acquire PDFs and she drops them all on the Desktop. Every time I have to do a cleanup, I will create a new dated folder on the Desktop and shove the latest crop in there. This keeps the Desktop clean and faster. All the stuff on the Desktop and in Documents got synced to iCloud. 15G of it. I had to upgrade her Mac Mini too, and it jumped about three upgrades to the latest version of High Sierra.
It took a week but eventually her old iPad and her Mac Mini were stable, synced and backed up. It was really nice. In total, between my data and backups, and Anne's data and backups, we used about 50G of the Family Sharing storage. I had a week of stability, I had everything back home separated, and the only things not done were Anne's current iPhone and iPad. I had to wait till she flew back here before I could tackle them.
I did an export from Anne's ownCloud calendar and contacts and imported them into her new iCloud Calendar on Contacts. Had to do that on her Mac Mini. Needed to do a little cleanup. Then I created a Family Calendar and added the details of our coming trip to it. I could see it on my devices, I could see it on her converted devices. This was one of the main reasons for going through all this - separate contacts and calendars, but access to a shared one.
First night back, I did nothing. Too late.
Second night back, I tackled her iPad. I switched it to her new Apple ID, turned on iCloud syncing and backup. It worked. Nothing was deleted, she lost nothing. Her photos on the iPad were automatically synced up to iCloud and then down to both her Mac Mini and old iPad. Then I upgraded to the latest iOS and let it settle. Nice. No problems.
Only thing was, she couldn't get any messages or Facetime on the iPad. The key that others used to message or Facetime her was the phone number, and that was still set to the iPhone. That had to wait till I did the iPhone.
Third night back, I tackled her iPhone. I switched to the new Apple ID. Her phone number disappeared from my Apple ID and switched to her new one. Her friends could continue to message and Facetime her. Phew. I added that phone number back to Message and Facetime on her iPad.
Then I turned on syncing and backup to iCloud on her iPhone. Nice. Took a while, but it all worked. Upgraded the OS to the latest version and she's all set. Almost.
So by this point, we were successfully split. Anne has her Apple ID and I have mine. We have Family Sharing so if we buy an app, we both can share it. We have separate contacts and calendars, but access to a shared calendar. Everything is synced and backed up.
I needed to deal with Anne's photos that had synced to my devices before the split. I made sure I had a backup of them, and deleted one on my iPhone. It disappeared from all my devices, but did not disappear from Anne's. I checked with a couple more, and left it an hour just to be safe. Gone from mine, preserved on hers. So I cleaned them all off my devices and all was well.
There were two remaining issues.
Anne's original two email addresses - AA@me.com and AA@icloud,com - were still attached to my Apple ID. These were used as alternative ways for Anne's friends to message and Facetime her if the phone number didn't work. The phone is a US phone number, and Australians sometimes couldn't send messages to it. But now they were on my Apple ID and not Anne's and if people tried to send to them, it would show Undelivered.
I went to Apple ID Management and those two email addresses were listed as ways to reach me. The question mark beside them showed that they were considered as aliases to my Apple ID. I could not delete them, I could not move them. I tried to do something about in lots of ways on different machines, but all attempts failed.
I put in a support request to Apple last night, explaining what I wanted. I had a reply waiting this morning. They said to make a support phone call. I did that this morning, and the Apple support person did screen sharing and I showed her what it was and what I wanted. Nope. Can't do it. Those two original email addresses are now aliases to my Apple ID and cannot be changed or deleted. Way back when I was merging her original Apple ID with my Apple ID, they became aliases and immutable. So that's my first fail. If Anne's friends find that they can't message or Facetime her, they will have to switch to the new Apple ID email address.
Second Fail That Turned Into A Success
Then came my second fail. On iPhone or iPad, if you go to Settings, Apple ID at top, iCloud, right down the bottom is a section called Mail. That's where you can set up official iCloud email. All Anne's devices have this set to her new Apple ID email - AB@icloud.com. Hers are all set up properly.
Mine is not set up right. I can't use my Apple ID because it's not an iCloud account. But it is set up to use one of my aliases, and that happens to me Anne's original email address - AA@me.com. I don't want that.
What I need is another alias for my Apple ID, an alias that is an iCloud email address. I had to research where this is done. I went to icloud.com and logged in. Selected Mail. Clicked on the little gear symbol at bottom left. Selected Preferences, clicked on Accounts at the top, and then there is an option to add an alias. I selected that and was able to enter an alias. I was able to enter a whole bunch of aliases and each was rejected. There's a lot of people with my name trying to grab names. In the end, I selected my regular name and added "real" at the front. That was acceptable, and it got set up. Great.
Then I had to add that alias to my Apple ID. There's a lot of steps to make these things work right. So back to appleid.apple.com, log in, and Edit my details. Anne's two aliases are still there. But I can add one more. I think there is a limit of three aliases. This "real" one will be my last one. I added the email address and Apple sent an email to it with a code. I logged back in to iCloud, picked up the email and got the code and added to the Apple ID website. And it was all good.
Final step was to change my devices so that the new alias is the preferred alias to use for iCloud mail. Back to my iPad, and I am interrupted and asked if I want the new alias to be used for Messages and Facetime. Sure. Back to the original task and go to Settings, Apple ID at top, iCloud, right down the bottom to Mail, and then select the new alias as my preferred email. And it took it.
So now that's all set up. I have Anne's two aliases out of use. I can't delete them. But all my devices can use my new alias.
I still have that second Apple ID and can't merge it with my primary. I could delete it, but don't really want to. Maybe Apple will allow merging of Apple ID one day. In the meantime, I will keep it active.
Leftover Apple ID
While I was going through this exercise, I wondered about the already taken names that I was trying. One was too specific, and I couldn't believe that someone else had taken it. I checked my security history document, and saw that I had that original Apple ID and those two email addresses - HA@me.com and HA@icloud.com. I had created them in 2009, and then forgotten about them. That Apple ID and email adresses still existed. I had the password and answers to security questions, so I logged in to it on icloud.com. It's valid. It's still working. But I can't really do anything with it.
Can I merge my regular Apple ID and this other one? Every thing I read says no.
Maybe one day Apple will allow merging of Apple IDs. In the meantime, I will keep it safe.
I was able to add the email address to Mail as an extra account, and that worked. Instantly I had 50 messages arrive. Half were from Apple - security messages starting in 2011 and continuing to today with my recent login. The other half were from my brother in 2015. He had invited me to subscribe to some shared iPhoto albums. I accepted the invitation and got to see the photos, three years too late.
In general, the operation was a success. I separated our accounts, got to share what needed to be shared, and got access to full iCloud features and benefits. There were a couple of minor unresolvable glitches, but we have workarounds for them.
All in all, success.