If the routing number changed, most likely there isn't anyone else with that combination of routing number/account number. It's like when your credit card is cancelled and you get a new number. The old number doesn't get reused, at least not for years. If a routing number changes, it seems like that would only happen if the bank changed ownership. In that case, the old routing number wouldn't apply to any valid accounts. I think more than likely the bank will route it back to the the correct account. If not, the payment will be refused and returned to
Fashionphile. In either case, you'll eventually get your money.