Noticed this whilst checking something on another forum. Might be of interest to people utilising the rail/sail option
"HOOK OF HOLLAND TO SCHIEDAM CENTRUM ROUTE CHANGES
On 1st April, 2017, the Dutch RET Metro Service will commence its operation of the Hook of Holland to Schiedam Centrum route on the Dutch Railway System, NS. All rail tracks will be converted to Metro lines and it is expected that the first subway train will run on 1st September, 2017.
From 1st April to 31st August a replacement bus service will be provided between Hook of Holland and Schiedam Centrum while track engineering works are in progress. Two services will run between Hook of Holland and Schiedam Centrum, a direct bus service and one which will stop at all intermediate railway stations en route. "