Is there such thing as letting bread rest for too long?
If you take a “fast” recipe and let it rest overnight, you will get overproofed dough. After what’s effectively eight times or more the expected time, you will have a rather yeasty tasting dough that has lost its inner structure - think of the way foam collapses after a while. It may or may not be able to do a comeback when re-kneaded, that will depend on the type of yeast you used and a few other parameters, especially the actual timing. 

But an overnight rest is nothing unheard of in baking - if you prepare your dough as usual but use cool ingredients instead of warm ones and significantly reduce the amount of yeast, you can let your dough rest in a cool place for hours, even longer in the fridge. If you have a very buttery dough, don’t cool it too much, or it won’t rise due to the hardened fat, choose “cool” (8-10 C) over “cold” (2-5 C)1. For an overnight rest, the flavor will stay pretty much the same, possibly less yeasty, which is desirable in my opinion. It’s the two-to-three-day (or even longer) rest that contributes to the flavor of baguette or the famous “Artisan bread in five minutes a day”.

Have fun! 



1Yes, that means you will be storing it slightly in the danger zone, but it’s up to you whether you want to take the risk. Overnight on the counter is way worse, the way yeast grows faster in warm conditions is the same as for bad bacteria. Personally, I am fine with that, but for the sake of completeness, it’s worth mentioning.