Hmm...I'm just going to take a guess so do not take this post as fact. Tbh I have little understanding of drug interactions/synergy, especially tianeptine which is a tca I believe.
What you should definitely avoid are MAOIs. SSRIs usually blunt the effects of mdma, and it would probably be safe to assume that tianeptine would too. Or at the very least, it would just be safe to assume that you shouldn't mix the two (tianeptine and mdma).
How long have you been taking this substance? Usually 2 weeks are the standard protocol for the amount of time needed for it to leave your system. But if you've been taking a high dose for a year or something like that, you should wait at least a month. This is to avoid any possible dangers of taking the mdma with it, or basically feeling nothing.
I hope someone else can jump in and provide the info you need. Be safe!
Edit: heh, just noticed that you were already planning not take it together. But yeah, depending on how long you've been taking it, a month should be fine. Or two just to stay on the uber safe side.