They may survive. Many evergreens have suffered from the long wet cold snowy weeks we have had with a few -10c every now and then. Just leave them and see if they start back into growth. Trachelospermum aren't 100% hardy but both plants should pick up. Don't trim them and wait till mid march or april for any signs of growth. If no signs during spring then they are probably dead.

I have three Sollya's, and all are kept undercover for the winter. Two are in the conservatory and one in the garage (owing to the recurrence of red spider mite). They were described as being tender below 5ºc, so I suspect that they may be dead......
I have just harvested a few seeds if you're interested.

thanks Nicky and Meanie, I'll wait until spring to see what happens. I protected them as best i could outside as they are climbers so were attached to trelis, so to have moved them undercover would have meant taking out a fence panel really, that the trellis is attached too. I did try to untie stems in autumn with the hope of moving it, but it was just falling about all over the place. I'll think things through a bit better next time i buy a non hardy climber! Meanie, thanks for the offer of seed, it is very kind. Although if i have lost them i know what i want to replace them with, and i have no other spare part of the garden to grow them again. But it was a very kind gesture. thank you.