I've been reading on some of the real navigation mods, and the issue they had with celestial bodies and the game's use of "local time". What I've experienced before with that is a loaded Save will sometimes take on the local "local time", in place of the 'Home time'. ie: Sunrise near Pearl might be 6:15a, but near Honshu, it's more like 11:15a. You play the game in your first sitting, traveling from Pearl to Midway to Honshu, and night is night, day is day for Pearl time, but might not be for Honshu time. You save the game, exit & come back the next day, and day is day now in Honshu, and you notice that you're on Honshu time, not Pearl time. Not always, but sometimes. Then, you've found that TC can influence how accurately the clock runs, with the game apparently not "locking" the 'earth' cylinder of the game with the 'sky' sphere of the game, apparently relying on 29.97 (30) fps to keep things synced. Seemingly related issues.
I have seen the loss of waypoints before on the navmap also, and got the game to do that the other day. Now I cannot replicate that. I've been shooting all over the firing range though, and have not been consistent with my "testing" targets. You seeing a possible link to the passage of time, as it relates to equipment availability, or something in the campaign is interesting. During the early phases of FotRSU development, we kept running into massive "convoys" of DD, groups of 18-30 in various places of the Pacific. We came to discover that they were improperly set Random Generated Groups (RGG) that were coninually spawning and joining their brethren as they mathematically looped the 'world', until the player got close enough to them, and they spawned into life. The game would stutter, drop frames terribly, worse than when near a large harbor area, and sometimes CTD. The further the calendar advanced, the worse it got. Resource hog. You made a point earlier about the 5" .25 cal., or maybe the AA, 'course, it could be a conning tower...
I'm going to concentrate all my testing near January 1, 1944, based upon what you've found, adding and subtracting one month at a time from a CareerStart, and see if I can get closer to a date when the time and equipment changes things. The 43a files load about 19430901, while the 44a files load about 19440601. Maybe the first "test target" would be a September 1, 1943 start... I'll add another "test" start to FotRSU, and PM you a link for that...
