Make sure you check your mail and junk mail every once in a while. The first response with be a generic response that usually has nothing to do with anything. And will end with if you dont respond we will assume this random nonsense we sent you fixed the issue, thanks!
Of course it will also be the second and third response from them, but fight the good fight!
That's really unfortunate. My issue is that Steam attached my ESO to my husband's Steam account and the two are linked together. He doesn't play; I do. He's been deployed and, even though he got a laptop for the deployment, he wasn't able to use his personal computer online (no Steam or anything) while gone so it was a non-issue until he got home 2 days ago. Even with Steam Family Sharing, only one person can play a game on the library at a time, so if he logged in while I was playing, it'd boot me off. Steam won't allow you to give games so we can't migrate the game to my Steam account. So I planned on just purchasing another copy of ESO for my own library and making a new account. However, because of my friend list/guild status, I'd like to keep the same UserID I have now (I do realize I will have to start my characters over, lose achievements, etc, etc which is fine at this point) so there's no confusion over me being...you know, me. So all I'm asking for is for them to change the UserID on the current account so I can then use the current ID on the new account. I know UserID changes are really uncommon and there has to be a good reason; I figure this might be one of those cases, especially since they'd actually be making more money off of it, rather than me trying to find a workaround. I'd been enjoying the game enough that I even considered purchasing a subscription for the first time. But if they can't answer support, I'm not sure that I want to bother.
Thank you to everyone that assisted and gave feedback, including @ZOS_DaryaK. Support got back to me and was able to change the UserID. It was a painless process once I got in touch with someone.