It is a flat-bottomed tin can.
I don't know the weather at the time, but if the waves was coming from the south, the ship would pitch up and down rather heavily, and make no headway.
So better keep the waves 45 deg on starboard and port bow.
But again I am not aware how the WX conditions was 🙂

It is a riverboat with poor seakeeping, so it could be true.

Godnat :)

hæhæ kommer i tanker om, meget meget historisk, at vi lå der med Neptun for 45 år siden, for at tage soldater fra Almegårds kaserne ombord.

Lad os se, det er næppe lystsejlads midt om natten. Men måske bare vagtskifte :)

Så dukkede P521 Freja op igen, nord for Rønne kurs W.

Hehe, but the Twin Otter just had a look NE of Anholt

Oh yes of course a TX typo. 56.6N it should be.
I was confirmation biased, and didn't even noticed it ...