I'm thinking to use my life miles to purchase UA tickets (international trip, Star Alliance). After the redemption, I still need to pay $200 fee using a credit card. If I use my United Explorer card to pay for the fee , will I still get 1st checked baggage free? I know if I purchase the ticket from UA's website using Explorer card (even for just the fee) there are no problems but not sure if I do the same from LifeMile's website, will I still get the 1st checked baggage free? From UA's website http://www.united.com/ual/en/us/fly/.../chasebag.html, it doesn't say it has to be from UA's website but must "Include their MileagePlus number in the reservation". So in this case I don't think I can do that from LifeMiles website. Or maybe after the purchase I can contact UA to add my MileagePlus number to the reservation and get free 1st checked baggage? This seems like a pretty common scenario but I couldn't find any answers from website. Thanks in advance.