Bro, if you see this offer detail on Channel 121: Recharge Information, the T&C mentions that the offer can be availed only once in a "Calendar Month". Hence, I think it should be given on both 31-Jan and 01-Feb. However, given airtel's track record, I doubt their language used in T&Cs too. Any confirmation by you or anyone else if really we need 30 days gap in between 2 recharges? Thanks in advance.