Help im lost!!!

Ok i got 3 plants that i transferred to MG 6 month release from FF about 2 weeks ago. problem is i am trying to flower in 2 weeks. I got some bunk soil from the store (FF not obtainable at this time) and i'm pretty sure that all soil comes with some kinda nutes in it (bat guano, earth worm castings, etc). Can i transplant this week?(It'll be officially my second week) After flushing the soil really well and letting it dry back out then putting my plant in do you think it'll be safe for a low amount of bloom nutes? Giving it a week (to recover) and going into flower or should i transplant and then flush the plant and soil together. They are soon to be a month old.

All help is MUCH appreciated and rep points!

sounds like a decent plan, you could cut the soil with 50 % perlite to lessen the nutes further.