I don't know what it is with mobile phone providers in the UK, but trying to get the PAC (port access code) references from them is sometimes a very long and drawn out process.

My own experience was with o2, it took over 3 months, and numerous calls to get the PAC from them, the normal routine was

call up
talk to a operator
request the code
get passed to another operator
get asked why i wish to leave
pass to another operator
get asked if they can do anything for me (i.e. cheeper line rental etc)
pass to another operator
the final operator to inform me that it will be on a text message in the next 48 hours.

normally the text message never got to me, so the whole routine started again.

So imagine when my better half seams to be having the same issue with Virgin Mobile, so far, she has called them 3 times, been told that it will be with her in 48 hours, the is not eligiable as her contract is still going (this is not the case) and then the last time the operator was confused as he could not see a reason why it had not been sent, so yet again we are on the 48 hour wait.