deltaforce,
Yes, the rule is only change one thing at a time.
Personally, I would not wait for the bleeding and other symptoms to stop before adding slippery elm bark powder. SLippery elm powder serves as an equivalent to 5asa... but your GI won't have a clue about it, as you said.
It's good you got the L-Glutamine powder.
Let us know how that works out for you.
I hope you start to feel better soon.