Stubhub guarantees a refund or tickets. Not saying that's ideal, but that's the reality. If the only replacement tickets are a lot higher in price, they will not replace your tickets and will only give you a refund. The other thing that makes it hard is Stubhub won't even check on the tickets until 3 hours before the event. So, unless the seller actually calls them and says they're not going to be able to fulfill the order, you can't know for sure or do anything through stubhub until right before.
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