Does anyone have word on whether it is a good move to purchase a certificate now ahead of the changes coming on August 1?
The direct answer to your question is "No, no one has word on this." Your specific situation (e.g. how much you need airline miles, how risk-averse you may be), may help inform whether this is a good idea for you, but no one who is talking knows what Marriott will do with the outstanding 7-night certificates on August 1st, or whatever date in August this magic switchover occurs. That of course does not mean that there aren't plenty of us with opinions. See the thread,Floater Certificates? for a sampling of the many opinions all across the web.
I personally have two 7-night certificates, one for category 6 and one for category 8 that are unattached and will remain so through the transition. Some on this site would tell you that that makes me very foolish indeed. However, if I did attach them, it would be throwing darts at the wall as my job does not allow me to plan lengthy travel any further out than I already have, and so I am not going to play the game of attaching and unattaching later. At the point that I bought each Travel Package, I was told by the CSR, a Marriott employee, that I would be allowed to use the hotel certificates after the transition and that I would not be hurt by waiting. Although I may be one of the few, I haven't had any major problems thus far with the way Marriott has handled this transition and I have full faith that they will treat us right on this issue as well.
I believe that my family and I will use 1) these certificates, 2) certificates that they are converted into, or 3) points that we are refunded for these certificates sometime in 2019 to have a fantastic 10-14 day vacation at great properties in Hawaii. If having that belief makes me gullible or foolish, then so be it.
That being said, you'll have to make the call if it is a good idea for you and as the days tick by, it appears more and more likely that everyone will be making that call without anything official from Marriott on the details.
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