Mix bag of grain

I am getting down to the bare bones as far as grain goes and would like to use up what I have before buying new. I would like to brew a chocolate stour and have all the specialty grains but about 1/2 of the pale malt. What would happen if I used pilsner malt for the other half?

You wouldn’t even notice.

I did this with a porter I just did on Sunday. the dark grains will cover any difference between the pale & pils malts.