Transplanting in flowering stage

I am currently growing some plants they are about 3 weeks into flowering and they have out grown there medium
is transplanting and option ats this stage as i think they mite be root bound ?

Any feedbak or tips on how i can make the exchange with the least stress possible will be taken wit great apprecation

All The Best !

I know you should transplant before flowering but it seems too late for you. If they are root bound you will have to transplant. Use some Vitamin B1 a day before you transplant. That should help with plant stress. I use Super Thrive when Im transplanting. Super Thrive has Vitamin B1 in it. Many people say not to use Super Thrive in flowering stage because it will make your buds very fluffy and decrease yield. So my recommendation to you is to transplant as soon as possible and use Vitamin B1.