Bumping at Gatwick ?
 

I'm flying out to Vegas later this week routing LGW ATL MEM LAS
Seatcounter shows D3 J3 S2 only so I'm guessing this may be a good bump possibility (Easter holidays and this is the last day before part 2 of the BA strike). There's plenty of availability on the LHR MSP LAS in the afternoon and plenty of time to cross to LHR as well as other possibilities.
I've never actively looked for a transatlantic bump with Delta before -so would appreciate Gatwick specific advice on this. I'm travelling with carry on only and will be there disgustingly early as I have a couple of audits to do landside before flying. As I dropped to FO this year for the first time I'm thinking the chances of an Op-Up are remote for a silver on an award ticket so a bump may be the way to go. Any advice on how to maximize my chances would be appreciated.

Thanks