Thanks for growing our Montreal. I'm relieved to read that you are up to flushing, because the plant looks as if it suffered from nitrogen toxicity.
Another reason could be a temperature too hot, but judging from your air day temperature this has nothing to do with the case.
Good luck anyway :) Hope you will tell us what it smells like.
@DivineSeeds_Consultant, plants were definitely dealing with too much heat so bang on there . Nitrogen shock is def possible as well. I get the autos dialed in yet