In theory it shouldn't be possible to be connected at the exchange to both, but I'm sure it happened to someone about a year ago. (It often happens on BT Wholesale migrations as those are just a swap of authentication and the new one can be up before the old one is deleted, but this is different).
Trouble is, if you stay on now you could have Zen internet until things get sorted, but if you try the new login and it fails you almost certainly wouldn't be able to get back on the Zen one as they will have closed the account

.
Just have to wait and see I suppose. Are vivaciti support contactable? I thought they went 24/7 a few months ago.
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