I think he will because I think at least at some point he was using some kind of PED regimen, and usually people who do that don't stop.
However, I don't want fights cancelled for bullshit like this last one. Thank God it was just moved, not cancelled. I believe in no punishment until someone is proven guilty and I'm still waiting for them to prove he did. So I support Jon in all of this because I think people are reacting moronically to what I see as a pretty clear situation. At this point, people are just taking pleasure in watching a man burn.
So the question is do I think he'll pop again, and my answer is yes because I suspect he's doing some kind of doping thing. But as to the question you didn't ask but everyone else is asking, which is whether he should've been allowed to fight, my answer is an unequivocal "yes" because A) they haven't proven he's (still) doping, and B) whatever's in his system isn't performance enhancing.
But if Jon never knowingly cheated and/or did cheat before but has legitimately stopped, then he probably won't pop again, unless in the off chance someone's basically poisoning him with PEDs as part of some nefarious plot. You asked what I think, so I'll say I just concluded that the odds are >50% IMO that he was cheating and will continue to do so.