Convoyers of the Admiralty of Amsterdam on 9 June 1652

I found that the specified number of 18 convoyers for the Admiralty of Amsterdam in 1652 is hard to prove. I can find 15 or 16 at most. To reach 18, I would have to count ships that were later funded under the 100 ships of 1652. The Edam and Star are prominent candidates, as they were both built as warships for the Admiralty of Amsterdam. On 9 June, there were only 11 ships funded by the 100 ships for the Admiralty of Amsterdam.