Thanks M
The routing is SIN - ARN.
I just checked the on time performance for QR943 and it is not so good, some a few mins early but also a few dates with delays into DOH.
https://www.flightradar24.com/data/flights/qr943
If my parents were to keep the SIN DOH flight and take the later DOH ARN flight, the layover is 11 hours. All other options also have a 8-9 hour connections.
There are better options via revenue on the day before and if QR could open up
one more award seat for SIN DOH it would be enough, as the DOH ARN flights are wide open with award seats
I'll call in again tomorrow and see how it goes, there's still a couple more months so maybe the schedule may change again. Thanks again in the meantime!