I'm a bit further along in the same career and I've found some more weirdly spawned ships whilst patrolling off the coast of Japan.
I'm in a Gar, it's May 5th 1942, ship locations are in the picture.
I came across two pairs of stationary ships, one pair very close to each other (a Composite Superstructure Freighter and a Ada Maru Old Freighter) and the other pair actually spawned through each other in sort of an "X" (an Old Hansa and an Ada Maru). They all stayed completely stationary whilst I closed and attacked. After 1 of the crossed ships sank the other started pulling away but was dragged down by the sinking ship and a torpedo I'd already put into it.
I don't have a save before I sank the first pair but here are some pictures of the crossed ships, and the map after sinking all 4.
On another note, have you guys tweaked the CO2 buildup whilst submerged? It seems to build up
really quickly now. I tested it and submerged at 1102 and got the CO2 alarm around 1600 the same day. I was just sat at 160ft doing nothing, not even moving. This seems way too quick to me?
Finally, do you still need people to check the gauges in the control room or have you got that nailed down now? If so I'll do the test and report back.
Edit: I also spotted that the bow planes aren't rigging out when diving on the Gar, even though they had previously been fine. I think maybe if I watch the boat dive in the free camera they don't rig out, but if I dive in the map view and go to free camera afterwards then they are rigged out? I need to test more to be sure.