Walking on water?

[Belphegor]

Please have a look at the screenshot. My Panzergrenadier Div appears to be able to walk on water to get to a hex behind allied lines. I have isolated the port but there is no land route to the circled hex. Is it just a display issue?

It's a server game (you'll have to use the backup save as I didn't try it out but did play on) vs S2_Tanker
I don't think I'm giving away much by posting this issue so let me know if there's another explanation too.

[Helpless]

Could it be that stack with HQ has no Combat Units in there and will get routed once you move to it? Did you try to move it?

[Belphegor]

It should have already routed being adjacent to my airborne unit. I could swear that hex with the HQ is a water hex and it is on transports (but it doesn't look like it)

edit: Yes, the hex in question with the HQ is listed as a water hex (162, 265)