I thought the idea of Managed Path was that it was aimed at those who were leaving at their 16/38 point. You were leaving the RAF anyway (eg. no PAS offer) so MP either got you a job (happy days) or it didn't (ho hum). Either way you had to leave the RAF as they no longer had a job for you there.... There is no Catch 22 about it - if you're staying in you take the PAS offer. If you're leaving you take MP and hope that a) oil doesn't rocket $200 a barrel or b) the BA cabin crew don't bring the company down in the meantime....
