Onion sets 2022

I've sown a row of senshyu seeds outdoors for the first time ever. They're popping up as we speak. Are they winter hardy? Never really had success with onions from seed, also never sown in autumn. What do I do next? I think the likelihood of neglect is on the cards. They'll need thinning I expect so I can hedge my bets and pot up the thinnings and keep them undercover I suppose.