I think i just found the answer myself:
On a Sony page thats not in the top hits when you search you can find an answer:
You may have noticed that on the back side of your Xperia 10 III, a technical model name is printed at the bottom, being either HQ-BT52 or XQ-BT52.
In other places, such as on the packaging or in the smartphone’s Settings menu under “About Phone”, XQ-BT52 should be displayed.
These 2 technical model names are actually product synonyms namely used for service, compliance and other purposes. Both represent official, standard issue and identical Xperia 10 III products.
So it seems this is the same product - and therefore Sailfix should be running.
Would be nice if Jolla adds this info to the devices page.
@tuplasuhveli just found the same link and wrote while you answered Thanks for your answer.