It is difficult to keep anything secret on the web ! The information came out via a MVCI ( Marriott timeshare) source.
I have to say I am astonished that the new policy has not been implemented immediately, unless Marriott want hundreds of millions of points bought in the last 10 days of the old rules !.
I have so many earned points myself that the change won't really affect me in the long run, but the offer was so good I have taken personal advantage of it whilst it was available.
I think Marriott should have left the uncapped buying facility unchanged for genuine loyal customers ( say platinums), and totally stopped it for the people who were joining Marriott Rewards just to buy points and then flush them out quickly as redemptions into other loyalty programmes. (Marriott must know who they are !)
By the way thank you to Rewards Guy for his posts over the last 6 months they have been very illuminating.
Tom