Changing times

Presently 3-4 weeks into a good flowering.
Lights on at noon, off at midnight.
Would really like to change them to on @ 9:30 morning, off @ 9:30 evening (getting cooler).
Would this mess them up now?
Is there a right way / wrong way do this?

My first indoor grow (outside just isn't safe anymore!). This has become more of a hobby than a grow thing! Must be the addictive part? - LOL
I think outside is easier,,,,, but this is much more,,,,, interesting(?).
Seems when I want to work on the plants / room in the evening,, people mysteriously seem to "pop-in" and I need to do a fast hide. During the morning is much, MUCH better for me (thus the 9:30 desire).

Cannabis flowers based on the amount of darkness it receives, so you can decrease the day time amount and be fine when flowering . Next time, turn your lights off early at 9:30 PM, then back on at 930 am. That should do the trick

Thanks.
Will do.

i want to switch from my lights being on during the day to being on during the night, any recommendations for that?

Well you can do it with no problems to the plant. Just make sure that when you do it that the calculation is more darkness than light. I would keep the lights off completely more than 18 hours and then get your new cycle going.

I would change it an hour a day to get closer to the target time. I changed mine going from veg to flower with a 24 hr dark period. I wouldn't change too much shit when your girls are flowering! You don't want it going sideways on you at this point.