Well besides using a service like experyflyer to check inventory, you'd have to call up Delta and ask if there is upgrade space available on those flights.
If I recall, they need to check in the AF flight number, not the DL codeshare. From other reports, AF is typically pretty stingy with making these available for DL upgrades.
I did a quick check using expertflyer and there is no O available for your dates at the moment.