This is the first that I have heard about Kent changing their formula. I did try Tech M twice when I was battling bryopsis in my 34, and it did not work for me either time. I was under the impression that it could be that there are different strains of bryopsis and some could be more resilient to whatever was in the Tech M that was supposed to kill it. Regardless, it was a waste of time and money for me. That being said, I do personally know of other people that it worked for, so take that with a grain of salt.
I also tried a myriad of other ways of eradicating it. I tried a lettuce nudi, lots of turbos, H2O2 broadcast dosing, kole tang, army of emerald crabs, etc.
None of them worked.
What ended up working for me was this:
I set up a simple 10 gallon frag tank. I moved all my frags/coral over to the frag tank in waves, 5 or 6 pieces at a time. I would do targeted H2O2 treatments on the rubble/plugs, then let them sit in the frag tank for a couple days and watch. If I saw more algae start to pop up, I would hit it with H2O2 again. A 5ml syringe works great for this. After I didn't see any more algae pop up for a good week or so, I would move over the next batch of frags. I am now toward the end of it and only have a couple frags left in the 34, which I will probably be moving over this weekend. I am happy to say that after a year of struggling with this plague, I am finally seeing light at the end of the tunnel. I will be breaking down the 34 and selling it off as I plan to do a simple downsize once all the coral it 100% in the clear.
I wish you good luck. This may not be the only way, but it was what worked for me.