Crew Promotion = undesired effect?

[The1stTropod]

Maybe it's something about the game that I am unaware of, but it seems more like a bug & I've not been able to find anything similar using search.

Description:
When promoting certain crew members & selecting a category for the promotion (eg torpedoes, engines etc) their other skill/specialization (the left one) changes also.
So for example: I would try to promote a crew member that has Command function & promote it to also have torpedoes function. And thus, the promotion ends up changing the Command function to mechanical (this is in addition to the added torp function).
Odd thing is, I can promote other crew members that are the same no problem, but with some others this happens.

Wondering if there is a certain (ranking) order or something that dictates promotions that might be causing this? Or is it a bug?
Thanks.

[The1stTropod]

Maybe it's something about the game that I am unaware of, but it seems more like a bug & I've not been able to find anything similar using search.

Description:
When promoting certain crew members & selecting a category for the promotion (eg torpedoes, engines etc) their other skill/specialization (the left one) changes also.
So for example: I would try to promote a crew member that has Command function & promote it to also have torpedoes function. And thus, the promotion ends up changing the Command function to mechanical (this is in addition to the added torp function).
Odd thing is, I can promote other crew members that are the same no problem, but with some others this happens.

Wondering if there is a certain (ranking) order or something that dictates promotions that might be causing this? Or is it a bug?
Thanks.

[Sparhawk81]

Do you have any mods installed?

It's possible that a promotion rises certain vaules, but lowers others...

Personally, I try to specialyze my men: sailors in the torpedo room will only be trained in torpedoes, for example.

And I haven't had any problems, so far...

On important thing I've noticed, before starting your first patrol, is to assing the right sailors to the right duty: I would never put someone with low mechanics and gunnery in the torpedo room, for example