I think the net reduction is two ships, as four Holland class large OPV's were delivered in the meantime. The two remaining M-frigates (VAN AMSTEL and VAN SPEIJK) will be replaced in the early to mid 2020s by two new ships in a joint programme with the Belgian navy, who also need to replace their two M-frigates. Likely, the four new ships will be built by Damen Schelde in Flushing, while the Belgian navy will coordinate a joint minehunter replacement programme for the Dutch and Belgian navies.

Rd77,, they build new ones,,or just reducing the fleet ?

Very nice! One of the two M-frigates that remain in the Dutch navy. The other six have been sold off to Belgium (2), Portugal (2) and Chile (2).