Transplanting/Soil Shock?

Hey guys, I have a couple of plants 1 week into flowering, I want to go ahead and transplant them to the 3gal containers I have, however, they have been in some miracle gro soil for awhile with time-released ferts, I want to transplant them to foxfarm ocean forest, if I transplant using the same soil i've been using, i'll be adding alot of time release ferts to my soil >_>. So if I do this will there be any problems? I just started flowering a day or so over a week now, bud is slowly starting to produce, since this is my first grow I really don't want to fuck my plants up! Worse comes to worse I guess I could pick all the time release ferts out of the mg soil, but i'd MUCH rather just be able to use foxfarm's. Any advice appreciated. Thanks

You should be fine. Buy yourself a small container of Super Thrive, if you dont have any. This will help the roots with the transplant, and hopefully avoid any major shock.

Try to transplant prior to flowering in future grows.