Heat,what to do?

I am running a single 600watt hps and lights on is at 8am, lights off 8pm(they are in flower). I live in australia and it has been getting hot(outside 29/30 degrees celcius.grow tent the same) just wondering if i can switch up the ligt schedule to say 5pm to 5am without them stressing???Thanks for your help

Sure you can. Just leaving the lights out for the extra hours it takes to get to the new on time.

thanks mate!!!! Just made my day,was starting to freak abit.