I did do that earlier this morning. It seemed to have maybe re-broadcast the payment, but I don't know if it used the higher tx fee? It doesn't seem like it did. At what point would it just return to my wallet?
Transactions are usually dropped from most nodes mempools after ~72 hours. However if someone is rebroadcasting the transaction, it may take longer or never drop at all.
Note that the Bitcoin does not return to your wallet (you won't see any transaction or anything like that). Rather what happens is that the transaction is dropped from the mempools and thus your wallet will revert to a state where the transaction never even happened. However you may need to have your wallet clear all unconfirmed transactions in order for that to happen (some wallets will continue to rebroadcast transactions).