Going through the same issue.
The lack of clear information is the worst issue, I just called O2 who said the port wasn't setup, I checked on the virginmobile website and in my account I found the PAC. I didn't get it via SMS either. Agent just said "put the new sim in and it will work on your old number"
Billing has been messed up (agent had to remove the 1Gig VOLT benefit and revert my account to Ultimate Oomph to be able to apply the discounts), this has resulted in a much higher bill this month (£140). The advisor assured me that next month I wont pay anything, and the month after would be reduced.
The whole renegotiation has been a real "faf"! Numerous calls, phone call cuts off after explaining the situation several times, whatsapp chats are frankly useless, I got a satisfactory deal I am happy with, hopefully the agent has done everything correctly to apply the charges, next few bills will be hard to figure out!
In short, there needs to be a procedure and clear instructions/advice to customers who are in the same situation as this, I'd guess may customers on UO with packaged virginmobile sims will be in the same situation soon.
Also, why do I have to have a separate O2 account (with credit check and direct debit), for a part of the Virgin Media package? Agent said it was a "soft" credit check, Ill check my credit score because I doubt a new SIM contract is subject to a "soft" check. The VirginMobile SIM had a separate account, but I didn't need a new direct debit?
Hopefully my number will port on Tuesday (too late for Monday now after 17.30 Friday).
Happy with my deal, its just took too long to sort it, and its still not 100% there!