There’s really no way to know for sure. Stubhub’s policy is that the seller has until 3 hours before the event to deliver the tickets. Unfortunately at that point there usually aren’t many tickets left for them to replace yours with. Plus, you have to call them 3 hours before the event since they won’t check with the seller until then and it takes lots of
time on hold, talking on the phone etc.
Even though it says 2 days before the event, if you call them 2 days before, they will say that the seller has until 3 hours before the event, so that date even doesn’t really mean anything. (I’ve been through this many many times and that’s my experience at least.)
Hopefully everything works out for you! There’s just no way around it that buying on Stubhub is a bit of a gamble. While many listings are legitimate, many listings are not and never get delivered.