The formular is quite secret.

I was told by SAS lounge agents that upgrade for points for flights far out (2+ weeks out) will only clear if the flight is already oversold in the original booked class OR there are award tickets available, like I class for business - so slim chance for the second.

Those requests will be cleared well in advance of OT. Anyway, if OT will report to SAS that there are x number of people willing to pay money for the seat, I guess they will just move around. :/

That is one of my main issues with SAS. While I'm a loyal frequent flyer with them, I feel kind of screwed every time doing some longhaul bookend in economy since there is 0 transparency on Opups, OT upgrades or EB upgrades.

So, for me it means that if I need to do longhaul flights in economy like for private vacation I go for some other carrier which in fact values status like UA. I ended up in C more than once based on status while on SAS metal I never ever had a single opup on longhaul while non status pax on dirt cheap eco tickets were upgraded