Talking of the CY @ Gdynia, the new combined MR/SPG award chart has just been published.

As I expected, the SPG properties have got more expensive but the Gdynia CY has got 2,500 points cheaper (20,000 to 17,500), the same as for the CY @ WAW.

The new rates are here: https://points-redemption.marriott.com/category-change
There's a great dynamic search tool to make it easy to search on country, etc.