So Pieter Allertszoon commanded the Burcht van Alkmaar at Dover?

Carl Stapel says that he found a reference that shows that Pieter Allertszoon commanded the ship Burcht van Alkmaar at Dover on 29 May 1652. This is another case where captains were moved around between different ships, so just because in one action or operation, a captain commanded one ship, that does not mean that he commanded the same ship in other actions or operations in the First Anglo-Dutch War. He may well have, but you cannot assume that fact. Presumably, the Burcht van Alkmaar is that ship that was lost in the Battle of the Kentish Knock on 8 October 1652.