Number Port Talk Talk to Sky

Hi, I have a question regarding the possibility of swapping numbers from an existing in use line from Talk Talk over to a new to be installed line from Sky. I took out a new line from Sky yesterday which is to be installed on the 21st May. The reason for this was that as Talk Talk is a LLU line there was a possibility of up to 14 day down time for both broadband and phone when the migration was made to Sky, this is unacceptable for me due to the need of 24/7 broadband accessibility. My contract with Talk Talk is due to expire, after years of poor unreliable service, in about a month. So with this in mind is it possible to transfer the old number on the talk talk line to the new sky line and if not is there any sort of number forwarding services offered by talktalk . Also if anyone has any other possible suggestions then they would be most welcome.
Thanks.

Just done this migration and at ordering time was asked if I wanted to move across the old number...and yes it was ported.

Downtime was a few hours on the same day.

When you say a new line, did you actually give them the details of the existing line, or is Sky really going to try and install a brand new line, rather than take over the TalkTalk service? If a brand new line, then that will cause you porting problems

Hi, yeah it was a brand new line install as I purposefully never told them that I had an existing line. Mainly due to the prospect of having to face down time, and the fact that if you get line rental, broadband, and phone from sky then you can get £65 cashback via quidco reducing the total cost and for only £10 installation fee it is worth the hassle. Yeah I thought there would be problems with this but wasnt too sure, its not really a big deal to me as we still have a month to tell everyone the new number who phones the current one. But I just thought I could make it more seamless, for myself and avoid all hassle. But thanks anyway, any help is appreciated.