Taking current mobile number to new network

[Twirly00]

I've just switched mobile networks over to O2 taking my current number and they said I would have disrupted service for most of today but it would be fine by 10pm. I just assumed this would be worst case scenario and that it would be up and running well before then but here we are at 10:30pm and I still can't send texts. Any ideas how long these things take to resume normal service?? I need to text!!