I wouldn't read too much into it. Probably came down to mundane things like when certain staff were available and wotnot.

By some accounts the Dutch authorities had been planning some kind of action since 1987 but it got put on hold after the mast collapse. (if true it makes a nonsense of the claims it was about the shortwave frequency). The action against the ship was totally unnecessary as the Radio 819 organisation (rumoured to be within weeks of bankruptcy) had been destroyed by the raids on their landbased office/studios (an aspect of the saga which there has been very little discussion about either at the time or in the years since) and once news/confirmation of this reached the ship Radio 819 would have been finished regardless.

The videos of the raid have always made for bizarre viewing. In the initial hour one sees most of the record library, studio equipment etc being meticulously packed and carried away but later on it degenerates into farce with the internal guts of transmitters being boxed and craned off onto the deck of the Volans in such a state that they might as well have just chucked the lot into the deep.