One of those outputs goes through a lengthy cable delay before connecting to the gate generator situated right next to the logic unit. Due to the long cable, the gate generator requires the signal to have additional amplitude or it will not respond. This means that the second output of that pair on the logic unit must remain unused or we will lose that signal. This delayed signal is the alternate time reference for the F1 TDCs; the main reference is the actual HMS gate (trigger) from the trigger supervisor. This extra reference may be necessary for some offline analyses, to eliminate some non-constant delay from the trigger supervisor, for example.
During (one of) the final trigger changes before the break, an additional cable was connected in this very output. It appears to lead upstairs. After consulting Mark, I changed that cable to connect to the inverted output instead. Should this turn out to be a problem, we can re-connect this cable elsewhere, resulting in a slight time delay but maintaining the signal sense. The now unused connector has been taped over to discourage its use, protecting the amplitude of the delayed signal.