Advice needed - Plants underwatered and possibly dying!

Yo guys, we had a couple of extremely hot days last week and i didnt realise how thirsty the plants were getting, i usually water them every two to three days, they are quite big now, in plagron soil in 18l pots, about 4 weeks into flower. I came to see them two days after i last watered and fed em, and to my horror most of em had fallen over in their pots and were all shrivelled and the branches felt hollow and limp. I watered em straight away and then every day for three days to try and recover them, the leaves are now almost back to normal but its been a week and they are still limp and fallen over in their pots? Is this a sign that they have had it or will they make a full recovery? I am about 3 to weeks from harvest and they dont look very well.

Help!!!

4 weeks into flowering and you gonna harvest after 3 ? that makes it 7 weeks for the flowering stage .. They may need more man !
And about the watering .. just continue giving water like you used to ( I water everyday with less quantity) and watch out not over doing it ! If you watering and they are still not recovering you have no solution ( If it's hot and very heated around them yuo will notice leaves curling up and changing color a little bit ! Are they curling up ? )

The leaves on some of the plants have curled up and turned yellow but they are still budding out ok.

Yea i meant 7 at a minimum, im doing a new strain (critical +) and sometimes ive been fine to cut after 7 weeks. might be nearer to 9 tho at this rate as we are having a very muggy summer and my tent is never below 35 celsius during the day! The heat is defo causing the problem. Thing is its the type of house that i live in that causes the heat buildup. I live in a 3 story well insulated new build, and i have the have the lights/fans on during daytime hours as the neighbours would hear it at nighttime as im connected both sides with thin walls. I have no way to extract the heat from the room with the tent in as i cant have a pipe going out the window becuase its too obvious. So the air extracts back into the same room, but as i have all my upstairs windows open constantly it creates enough of a through draft to carry fresh air in. Also have a thermal storage heater in same room as tent so its constantly hot in there becuase of that aswell.

Really i should consider moving house lol. Its not ideal at all.

So I think you just keep going with same stuff you doing ! Just make sure nothing is disturbing their process !