Your odds are miniscule.

If Y is oversold they will start bumping up Medallions but they'll start with DM's on higher fare classes.

FO on a V fare is about as low as it possibly can go.

If J is really empty they may offer a buy up but that's getting increasingly rare for DL as they'd rather take the hit on an individual flight than let it become common practice and everyone buys a VXT fare for $1,100 and a buy up for $500 instead of selling outright J for $3-15K.