Well this is a bit what I wonder about. I have done a fair amount of SAS intra-Europe flights and sure I have got a few op-ups due to full flight but they were done at the gate.
I have also been re-seated onboard when economy extra was almost empty and P-class crowded, they have allowed me to move forward to get a bit more space by moving the plastic divider.

I have never ever experienced anything similar to this though, the only passsenger in economy extra being upgraded to business and four passengers in P-class being upgraded to economy extra by the purser.
Is the purser really allowed to make these kind of decisions? Perhaps a policy change?
Considering they haven't even been willing to offer me a cup of coffee for free as EBG in the past this was quite a big step, a full upgrade in every possible way.

Well it was certainly not a bad initiative, it was a great one, the lack of recognition onboard is something that has been widely discussed here for years.
It was also very obvious the purser/FAs knew very well they had upgraded four EBGs (i.e. very loyal customers) and really wanted to make something good out of it, thus providing significantly above-average service.

Perhaps it would have been better to do it at the gate, but in this case it wasn't, so would have been better not to do it?
Seemed like a lot of economy extra passengers did not show up, so they got an almost empty cabin and a few extra meals they would have to throw away.
The paying premium passengers were not affected at all in this case, I am more concerned what the P-class passengers thought.

Good suggestion!!