FWIW, last year was the only time I have seen that promotion. I would suggest waiting until May as the promotion went through the end of May last year. Also it was an AA promotion, so you may want to search for Marriott 20% or Marriott Bonus on the AA forum to see if it was offered in previous years. If it was, there is sure to have been a post in that forum.
I this is for an award this coming year, either wait and don't have the points taken out for the reward, or if you have a plethora of points you can take the points out and then have a MR CSR replace it with a travel package award later. The later is what I did last year, as I had already planned my award prior to the offer coming out.