my family of four has a trip out of ICN in a couple of days. two of us are flying prestige class so we know we have prestige lounge access. one of the two is also morning calm, and according to the website, we are allowed to bring a guest. our plan is to ask if we can bring two guests this way, but it's possible they will only let us bring one guest with morning calm privileges.

one of the two who are flying economy happens to have enough skypass miles to buy a lounge coupon. we know using 4000 skymiles is not a great value, but these miles will expire soon anyway so we're unlikely to get any other use out of them.

my question is: if we redeem miles for a lounge coupon, will we get it immediately, or is there some delay? i would hate to use the miles, only to find out after redemption that they do something weird like mailing the voucher to us.