Light help

Basically due to a certain circumstance I have to turn my lights off at 11.30 they are in pre flower and I do 8.15-8-15 when I put lights back on should I turn them off as usuall at 8.15 or leave them on for te time they were off so say they were off for 2 hours should I turn them off at 815 normal or 1015 as were off for 2 hours??

It was likely based on theory back when I needed to think about it Ganja but it is the night length that matters in flower stages. I'm never too fussed about a longer night and would just return to the usual ..but more careful shortening the night, maybe this helps.