Just checking we played this right as the rulebook seemed unclear. Can a player activate a system adjacent to their upgraded PDS not move shots in and just shoot an opponent's ships?

Yes they can. Generally a waste of a Command Counter, but with the right tech it can work

Waste of Command Counters or not kinda depends on how many PDS units you have in range. If, say, the Xxcha have ALL their PDS AND their FS in range it could be VERY worth. Wiping out most of a fleet with 0 risk to your own ships? Sounds worth to me. Situational, I know but still...

I sometimes did that to shoot at an incoming fleet. Frequently it's worth the cost if you have the right tech.

I've encountered another question about activating PDS:
Since activating Space Cannon Offence is a substep of " Step 2 - Movement" during player's Tactical Action, does it trigger if another player activates system adjacent to mine with PDS II and chooses NOT to move any ships into the system while having one or two there?
My point of view is that I can shoot whether they moved ships or not, .
Another player supported with others say that if they don't move, then the whole Step 2 is skipped an I have no timing window to activate my PDS.
What would you say?

Anyone with PDS:s in range of an activated system may fire into the activated system regardless of wether any ships moved into it or not.

23 hours ago, Fnoffen said:

Anyone with PDS:s in range of an activated system may fire into the activated system regardless of wether any ships moved into it or not.

Tanx a lot for fast reply