Is there a point where controlling fermentation temps isn’t critical? If I keep a beer at say 65 for a week or until the active fermentation died down and then take it out of my fermentation chamber where it may rise to 70-80 would undesired ester production and off flavors be much of an issue? I’m trying to reduce the time a wait between batches because I only have room for one fermenter at a time in my chamber.
Short answer, yes. If the recipe calls for an ideal temp of 65, you will likely get undesired ester production/flavors if the temp were to rise to the high 70’s - low 80’s. Not to mention, raising the temps to that range may prolong fermentation, resulting in a lower final gravity than desired.
Now, more experienced brewers than myself could likely provide more detail as to the specific effects that changing temperatures may have on you beer. What type of beer is the one in question, and what type of yeast are you using?
After a week at your desired fermentation temperature, you shouldn’t be worse off letting the temperature rise. The flavor profile locks in after a couple of days.
This^^^^ the first couple days to a week are the crucial times that off flavors are going to develop. A rise in temps can actually help the yeast finish and clean up by products created during fermentation. I will warn you that warmer temps will speed up the aging process.