Do yellow leaves serve a purpose?

So I'm 6 weeks in on an 8 week flowering period of ten Big Buddha Cheese.I fucked up early on in flower by not supplementing the girls with enough nitrogen and loads of the leaves turned yellow but managed to almost recover by giving them a nitrozyme boost.
Now,I know from previous grows that late in flower leaves do turn yellow on some strains but because of this early balls up I've got a lot more yellow leaves than usual.
What i'd like to know is do these yellow leaves still serve a purpose for the plant?They're not dry or crispy just a normal feeling leaf that's turned yellow.All of the fan leaves are now yellow and lots of the lower yellow leaves are blocking some light from getting to the buds and green sugar leaves.
Do I remove them or let the plant do it naturally bearing in mind i'm two weeks from harvest?

Leaving them alone will be fine, they may still be generating some energy.

Hey 1djwesty. I have concluded that if a gentle tug of a yellowing leaf makes it come off then that is fine. But if you gently pull and it is still attached and healthy feeling leave it. These leaves are the powerhouses for our plants and even if they are ugly, they are still aiding in plant growth and processes. Hope it helps

Thanks guys for your input.Grateful Joe,that's exactly what i'm doing at the mo,gentle tug,if she falls off super easy off she comes,if there's a little pulling force leave 'em alone.