By ferry or Eurostar instead of through Schiphol
Not everyone lands at Schiphol. From the UK, the ferries from Harwich, Hull and Newcastle arrive at Hook of Holland, Rotterdam Europoort and IJmuiden, and the Eurostar runs from London through to Rotterdam and Amsterdam. On all of them the Netherlands pack starts only when the phone first connects to KPN or Vodafone on the Dutch side: it gives nothing at sea or on the stretch through France and Belgium.
That is fine if you only need data once you arrive. Before you board a ferry, turn data roaming off on your own line, so it does not attach to the ship's network, which is outside the EU roaming rules and billed separately. This is also why the pack suits UK travellers in particular, along with visitors from outside Europe: since Brexit, a UK plan may charge for every day here.
