transplanting question

Have 2 females not sure of exact age, veged them for about a month maybe a little more and then been 12/12 under a 150w hps for 15 days. They are about 2.5-3ft tall, been feeding them tiger bloom and big bloom since switch to flowering. They are in about 1x1 pots and need transplanted, is it to late since I switched to flowering?

You can still transplant during flowering. Its mostly advised against in case you fuck up and damage your root system, which will stunt your plants growth for awhile till it recovers. If you are careful, you can go ahead and transplant if its really necessary. Just be gentle.