I am running into the same situation as OP. I took almost a year off from work and flew a lot on QR & AA J class. My membership cycle ends in Sept, but by end-Feb, I would have already got 100k CP. My dilemma here is if I should get all my flights (from Mar-Sept) count towards 17/18 DM qualifications or save it for the 18/19 membership year. Given I won't travel as much this and likely next year, I should only marginally make to DM for 18/19 and will definitely fall back to GD or mid-SL in 18/19. I usually fly the cheapest available J class on long haul and lowest Y or redemption on short haul. I usually arrive HKG just 1 hour prior, and my favourite lounge food is dan dan noodle instead of fancy meals, so I am struggling if DM memberships give me a lot more value versus money spent & effort. I am also running into another problem of having too many AM. Would be good if anyone can share your wisdom