When to reissue...?
 

I have flown 2 of 20 segments on a DONE4 ex-ARN and need to reorder my next 4 segments (fly 5 and 6 before 3 and 4). It would be really helpful if I could defer reissuing the tickets until after I fly segment 5 as I will possibly need to make changes further down the line and will be able to make a better decision on that in a few weeks. My paper tickets are arranged as follows:

Ticket 1: segments 1 and 2 already flown
Ticket 2: seg 3 (HKG-DPS), seg 4 (SIN-xHKG)
Ticket 3: seg 5 (HKG-KHI), seg 6 (KHI-xHKG), seg 7 (HKG-xAKL), seg 8 (AKL-BNE)
Tickets 4-7: segments 9-20

If I were to cancel the reservations for 3 and 4 (or change the dates to between 5/6 and 7/8) and remove Ticket 2 from the stack, from what I understand I should be able to successfully use the coupon for segment 5 without reissuing. But could I then add Ticket 2 back in and take it to be reissued, keeping the 17 segments not yet flown?

No...