Veg and flower

If your strain has an 8 to 11 week flower time then how long before I should turn my lights back to 12 + 12 also when I turn them back do I get rid of thousand watt metal halide and convert over to thousand Watt HPS and can I run 5000 watt LED full spectrum lights with my high pressure sodium bulbs at the same time to cover a bigger area

not sure what you mean by turn them BACK to 12+12 they should be on 18 hours in veg then 12 hours when you flip them to flower.... and when they on flower yes you wanna get rid of your metal halide to a duel spec bulb like a hps or led long as they both duel specs pretty sure you can mix the lights up tho to cover more light how many plants are you doing under these lights?