It's a bit early for sowing toms out in a polytunnel or cold GH really, but worth just a few seeds because even if they don't thrive, you can always sow well up to mid/end of March if it looks a bit dodgy with the weather! You never know, the seeds you've popped in might take a day or two longer to germinate, and when they get going, we might have got over the cold spell, and you'll be away!
Why not keep a few seeds back for a later sowing, just in case - that's assuming you are allowed to keep your slot open!
