I can't say definitively, but I think it is fairly random whether a Crohn's relapse will occur after stopping a biologic. Remicade has the longest half life, so it would take longer for a relapse than others. The good news is that the other biologics are fully humanized proteins, unlike the mouse based protein of Remicade, so less likely to produce allergic reactions. Plus, they are sucutaneous injections, not IV infusions, so they enter your bloodstream more gradually.

It is typical to stop biologics abruptly, so don't worry about side effects of that. As I mentioned before, Remicade stays in the system a long time. The main thing about stopping Remicade is that usually, it is felt that you cannot resume it at a later date because of antibody formation. But, it seems that is not likely for you, since you already have an intolerance. 

I have switched from several biologics (Enbrel, Humira, Simponi, and now Cimzia). I just stopped one and started another without issues.

Jan

I stopped remicade "cold turkey" and it was fine. No side effects. 

I had a 3 year remission stopping remi cold turkey