Originally Posted by
msuroo
Yes, changing your preferences happens immediately, but my experience is that your earnings will be based on your preferences at the time that your points/miles post, rather than your preferences at the time of the stay.
For example, check in 9/28, check out 9/29. Check into a new hotel 9/29, check out 9/30. On 10/1, points post for stay one. Switch earnings to miles. On 10/2, miles post for stay 2.
Thanks! Do you know if MR points post more quickly than airline miles? I seemed to get that impression on one of the Grand Slam threads for hotels in general (i.e. not specific to Marriott). I'm worried that they might only do a 'sweep' for airline miles, say, once a week and all my stays end up getting credited on the same date.