Ok, so Synopsis of last day events:
CMDR Delmonte made 3 recordings of his T7 full of all the rares in game: for each recording he eliminated a particular rare from its Hold.
Scientific Data, Soontill Relics, Occupied Cryopods.
https://forums.frontier.co.uk/showthread.php?t=195658&page=62&p=3049055#post3049055
I've decoded all of them and the UA was still spelling the Station's name.
Then a thought came to my mind, so I went to meet him in Thompson Dock with my DBX, equipped a T7, and he gave me his UA.
My T7 was empty holded, fully armed (4 pulses), and with my surprise I discovered that the deployed UA in front of me was SPELLING THE NAME OF THE STATION as well.
Then I decided to do the DEFINITIVE experiment:
https://forums.frontier.co.uk/showthread.php?t=195658&page=66&p=3050462&viewfull=1#post3050462
In short, swapping ship from T7 to DBX,
while leaving the UA floating outside the station, revealed that, if deployed from the DBX,
whatever the listening ship, the UA spelled the drawing MORSE.
If deployed from the T7, instead, it spelled the Station's name,
whatever ship was listening to it.
BAM.
An other important thing that I discovered thanks to this experiment is that, if you want to swap ships while still carrying an UA,
YOU CAN:
just jettison it outside the station, change ship, scoop it again
Now it's time to test all the other ships, with Asp and DBX already deeply tested making the UA spell the Drawing.
further thoughts: yes it could be a bug, but it's unlikely, because the T7 produced both MORSES, not just the Station's one.
And most important, we can definitely say that both UA behavior, drawing and spelling station's names,
are still present in 1.4.