Yes that is my interpretation as well. ROS starts immediately but you have to do five years on PAS to get the pension and don't go onto it until your current engagement expiry date. The wording was not immediately obvious and it was only on reading the certificate you send back that I became aware I would not go immediately onto PAS.
Anyone know if PAS would now come with a tax hit on the annual allowance for pensions? Reading the wording in JSP 754 doesn't make things any clearer to me but then I am just a pilot!