Is that not a GROM banner hanging in the picture ?
Nope, it is a banner of another Polish special forces unit. This unit is much older than GROM.
The banner on the wall of the building is the big clue I mentioned in my post #987, but there are also some smaller ones.
Should I have said, October 8, 2018 ?
No, it's about October 8.
There are a couple of significant anniversaries at this time.
But connected to this unit?
The photo is very telling - there's everything one needs to identify the unit, including which sub-unit those guys in the photo belong to.