Here is post from One Mile At A Time: (much thanks to Lucky)
Existing Travel Package certificates can be redeemed starting today
Initially Marriott said that you wouldn’t be able to redeem existing Travel Package certificates until September 18, 2018. This one month period where you couldn’t redeem was supposedly due to potential issues Marriott was worried they’d have with their new technology.
As it turns out that isn’t an issue and they’ve completed the testing necessary. As a result
you’ll be able to redeem existing Travel Package certificates starting today.
Some members can get partial refunds on Travel Packages
Members who booked a Category 6, Category 8, or Tier 1-3 Travel Package can receive a one-time exchange for a package one category lower.
The reason this is being done for these categories is because in all cases you’d get the same value if you had booked a hotel that’s one category lower, so as a gesture of goodwill Marriott will refund 30,000 points per certificate for those who request it.
This one-time exchange can be requested by
contacting Marriott at this link, and selecting the “packages – deals” topic.
You actually have until these certificates expire in order to exchange them, and once you do, the certificates will once again be valid for a year, so you can potentially make that work in your favor.
Trade existing certificates for points
With Marriott Travel Packages you’ve always been able to exchange your certificate for a set number of points, and this will continue to be possible for existing certificates issued prior to August 18, at the same rates as before.
Category 1-5 certificates can be traded for 45,000 points, and higher level certificates can be traded for 45,000 points plus the difference in cost between certificates.