I agree with this 100% While FBPB might not be as much of a raw threat as it was in AC, the simple fact is once she gets a 22D off, ANY random hit (or grab, something that she didn't have in AC) will lead into high damage, knockdown, meter to 22D again OR strong okizeme. I believe as of now it's a harder to set up her amazing corner oki from AC, but I have faith that setups will be found.
And mind you, FBPB is still very much a threat once she has a Ryujin card, if not moreso. A change to FBPB is giving it one extra frame of invul, meaning now the attack cannot be stuffed after the invul starts.
Jam'll probably end up being in the A tier among other strong characters, possibly S, though I don't believe she has anything now that puts her into the "AC Eddie/Testament" tier. She still requires a strong neutral game and fights from a spacing disadvantage against many characters. Although, with ACR, I don't think anyone is AC Eddie/Testament tier.