Should I flip in Flower ?

Flipping to flower depends, it seems like they are filling up space so it might be a good time it really depends what you are looking. As for me i'd wait one more week or 2 but thats just my liking.... i like them big fat Colaas.. : burnt tips probably due to too much nutrients let the soil dry out and monitor the nutrient levels if the problem continues, flush the soil with distilled water then right after flush replace with a 30% strenght nutrient and water solution monitor them for couple days, again try giving a lower dose of whatever nutrients you are using. and if you want to feel free to messege me in future. happy growing.