If you create several different offers, sometimes In Cart Upsell may show a different offer than you are expecting. To avoid overwhelming your customers, we show only one offer at a time. Here's how the system decides which offer to show:
If multiple offers fit a shopper, the system chooses the most specific offer that fits (ie. the one with the most rules)
If there are multiple offers that fit and they have the same number of rules, one of those is chosen at random.
So if you prefer that a certain offer be given preference, you can give it "dummy" rules, like "Cart total is at least 0" or something - or if you want offers mixed up randomly, try to give them the same number of rules.