I just received an email from the upgrade-plusgrade from Aer Lingus on my flight #124 and #125 ORD-DUB, DUB-ORD, minimum bid $420. No u/g on the CLE-ORD, DUB-LHR, CDG-DUB, or ORD-CLE was available. Total cost for all these flights was $900 and change.

Should I give it the minimum bid? If not accepted than no worries, but they want my CC#...doesn't EI already have that info? Is this really legit?