Hi There - I have grown Senshyu the past couple of years. I think you have missed the boat with seeds, so I recommend you save them for next August. I suspect transplanting won't really do, but there will be some one with more experience along soon.
However.....it is not too late for garlic (see thread below) or overwintering onion sets.
And there are other things you can try under fleece/cloches. I sowed a few more carrots and turnips yesterday in the open, and some lettuce and radishes in my little fleeced bit. Good luck!
