I'm on turn 9. A0 hasn't moved. B0 hasn't moved. C0 hasn't moved. However, B1 and B2
have moved and Sx also. The distances cited are where the units presently are.
Found this in the v5 Game Guide:
Unit Communications Status, On the unit information pane at the bottom of the screen, the unit's comms link status with its superior HQ is now noted. The selected unit shown is 'In Contact' and so will be able to be rallied by its HQ, however if it is out of contact (shown in red) then it can only be rallied by its own leader. Radio contact is OK, but the link is not 100% reliable!
I understand CHQ link status is evaluated at the beginning of the turn.
Based on that and what Imp & Mobhack have said: 'in contact' means solid CHQ link, i.e., either verbal or by radio (in the latter case you gots all the bars). If yellow R you have CHQ link by radio only, but you gots only some bars (your call
could be dropped), i.e., potential gibberish, static or congestion on the comm link.
at the moment a rally attempt is made - with yellow R - either the superior
might not hear the sitrep (rally call), or encouragement / directives might not be
received by the subordinate in need of rally. Just speculating on all that.
Based on my understanding of how rally works, in the latter case the superior would get relieved of rally points ('cause a rally went out from the superior), but the subordinate would fail rally (rally didn't get through). In the former, the superior no get relieved rally points (never heard sitrep needing rally so rally never issued), subordinate fails rally (no rally made it back to subordinate from superior). I have no idea if the game engine is sophistated enough for that.
My understanding of how rally works is that the superior is relieved of rally points for each
successful rally. When superior's rally points goes to zero, subordinates can only rally themselves. This implies that the subordinate has to make a 'savings throw' in order for a rally to be successfull. If the subordinate fails its savings throw, the superior loses ALL their rally points (and can not rally any additional units).
Perhaps the game engine is simplistic in the sense that a yellow R decreases the subordinates 'saving throw', i.e., increased odds of rally failure and ANY failed rally will result in the superior losing all their rally points.
I'm just trying to get the handle on what "not reliable" means in comparision to "in contact". Because you can be in contact and fail a rally, no? If the simplistic case is the truth of the matter, that's
bad. A faulty radio comm link buried in the middle of a comm net that results in rally failure will ALSO spoil rally for ALL other subordinates that might be in need of rally by that superior; they'll only be rallyable be the next superior subordinate to that one, or themselves.
I could see the simplistic way of doing it too though. Any failed rally regardless of cause - flakey radio comms or not - will result in the superior having a nervous breakdown and be unable to rally anybody else for the rest of the turn.