I was looking to do the Diamond challenge (or match, but I heard they were rid of that now?) starting here shortly in January, which I may or may not make (depending on if plans solidify). However I have some basic questions:

Main reason I'm pushing for it in Jan is because I have a special stay booked on points/certs for the end of February with the girlfriend, which I would love to make as unique and great as possible, so figure being even a temporary Diamond (if I don't make it) would be worthwhile.

Now, the challenge is 60 days where I will be upgraded to a Diamond, and receive all Diamond benefits, correct?

Are there any advantages to booking stays while a Diamond or is it more advantageous to be a Diamond while actually at the property?

Is this a bad strategy? I know there's only a single challenge allowed, however due to the nature of my stay in February, I figure it will be personally rewarding and hope I can still manage to complete the challenge as well, however I'm pushing that there will be a real benefit for my stay in February and a possible benefit for a stay booked while a Diamond.