Will 3 regard me as a new customer if transferring back from iD?

nottsphil

I was with Three until a couple of years ago on SIM-only but now I want to return, simply because of a generous TCB Black Friday offer. 
Will I have any problems transferring my existing number over?
Thanks.

GrumpyDil

Nope, you will be seen as a new customer. 

nottsphil

In the buying process I tried logging in with my old Three details but was surprised to find that it came up as 'email not registered'. I then made a new account with a different email address. I got it verified, and Three even sent documents to it, but when I tried to use it for the purchase it came up as 'email not registered' again! Completely bizarre. I then switch from iPhone to a laptop, but registering yet another email address came up with a red 'Somethings gone wrong. Please come back later and try again.'
 Looks like I've lost out on my TCB deal as it expires at midnight, and they've lost a returning customer.