I've been watching some seedlings, these pots started with my sheepsbit plug plants but I see these fatter-leaved seedlings, are they earlier sheepsbit? I'll continue to watch and see how they develop.

I bought some sheepsbit plug plants last year. I potted them up, some died, I have 4 pots of them now, left to right, black pot with seedlings not looking very good, turning brown, next orange pot looking good, black pot on the right looking ok, above that the pot has been invaded with poppy seedlings and maybe others. The last time I tried to remove unwanted seedlings it was a disaster so going to repot the entire pot in a larger pot and hope both the sheepsbit and poppies will bloom. The other three pots in the row above, black rectangular pot globe thistle and a wall lettuce, selfheal and claytonia in the black pot and hairy bittercress and a poppy in the orange pot.

closer view

the sheepsbit which are not looking very green, I don't know why when the others look very green and healthy, I suspect wood avens self-seeded but want to grow on to confirm

I took all those suspected wood avens and green alkanet and potted them up