I have exactly the same problem with PAC code and EE number not transferred by THREE despite their repeated promises that it will be transferred without any problem!
Called almost every day for a week, Three says the port was successful yet voice calls go to my OLD EE voicemail (on a different phone). They send a new simcard, again stating everything is ok while it isnt.
I called EE and they say that THREE hasnt undertaken the transfer correctly (a known problem apparently).
Why is it so difficult to get my number transferred correctly? I will be looking at cancelling my plan in the cool off period because this is mad
