While testing the latest Beta of TheShotte's SW1500 addition to the Oakville route, I decided to run the L79131-05 Burlington Yard Switching session, which involves loading some tankers and requires coupling to a rack of the same. As I usually do, I checked the 2D map, where this oddity appeared: The screenshot's caption explains the oddity, which is not something that even he can fix with a mod, but caused me a bit of head-scratching before I discovered the existence of that switch.
I noticed this too in a recently play on Oakville. Perhaps it will be fixed in the preservation crew update