I'd guess every Credit transaction which is not a payment (cash, check, wire transfer) would lead to a debit on the miles. I am not sure how they should handle this, so drop them a line, since you know how their staff is trained if you call the call centre
Maybe also for the other credit on bonus miles.
I did and this is the reply (there should be a crying smiley for these situations)
Dear sir, This is with reference to your query dated October 25, 2012. 1. Please find the earning ratio: * 10 Premier Miles for every Rs. 100 spent on airline purchases made at airline websites, airline counters or via booking options offered to you in the Premier Miles website (
www.premiermiles.co.in) . This will be capped to a spend of Rs 5 lacs in this category for every calendar year. Calendar year will be counted as Jan- Dec every year. * 4 Premier Miles for every Rs.100 spent on bookings made through any Travel Agents, including but not limited to any private travel agents, corporate travel agents, Online Travel Agencies or their websites/IVR systems NOTE : Any bookings made through any Travel Agents, including but not limited to any private travel agents, corporate travel agents, Online Travel Agencies or their websites/IVR systems, shall only be eligible for 4 Premier Miles for every Rs. 100 spent. * 4 Premier Miles for every Rs. 100 spent on all your non -airline purchases 2. Subsequently, we have received direct credits from the merchant. Accordingly, the amounts got credited to your card account and the corresponding Reward Points given to your card account has been debited
I never even touched the subject of how many miles I earn for Airline spends and neither was the refund from a airline.