Pinching out cosmos

I saw a YouTube video suggesting that cosmos should be pinched out when they have 7 leaves. These are a lot smaller than that, but 3 of them are starting to flower. They are a nicer green than this in reality, the light is odd in this picture. Should I pinch the tips out now?

 

I would usually wait until they are bit bigger but if there’s a bud then I would pinch now or the energy will be going into that and not making roots and leaves.

 

That reminds me I havnt sown mine

 

Thanks