Me too! I tested yesterday and rank is still working in Odyssey. Will try to test today running missions in Horizons then check display in EDO to see if its just the display that’s borked. Counted them yesterday from my EDDiscovery history and it took 65 Rep+++ missions to get from Cmdr to Captain. Only done 14 so far at Captain, so a way to go before I’d be waiting for the VAdm rank mission to get my corvette.
My EDD history for primary account is showing fed/Imp ranks as 26, 24, which is nonsense as there are only 14 rank values for each. They should be 13,12 (Vice Admiral & Duke). So clearly there’s a bit shift in the Horizons code rank enumeration for display which is going wrong and out of bounds so it cant display them correctly.
EDIT:
OK, have just completed a couple of Fed REP+++ missions in my primary account within Horizons and then moved over into EDO, where my rank is shown as having moved up from yesterday's Vice Admiral 21% to 25%.
So the mission rep within Horizons IS being counted just not properly displayed in Cmdr stats, and, I assume, therefore may not trigger a rank-up mission when you get to 100%.
I shall return to ranking up my second account in the hope that this bug is fixed soon, my clone wants his 'Vette!