Ok. I found the below post that Trevally made a few months ago when I asked the same question then. To confirm, we have to always use the dials and not the XO text box? While this will help, I still consider it a bug that would be great to fix. The AOB should always persist across stadimeter calls. At least it always has in past SH games.
I'll try this when I have time. Thanks again Trevally.
"If you are using TDW UI and you send AOB to TDC, it will stay set.
Adding range by stati wont change this setting.
If you MOVE your scope and take a range - AOB snaps back to pre-set.
To get around this:-
Set AOB and send to TDC. as ship move, AOB will track.
Just before taking your final range reading - open TDC and move AOB up or down a few deg, then back to where it was. You can now use stadi for range as long as you dont move your scope.
This bug will only happen when moving your scope. (I think)"