Question about in-game plane info (combat debut)

[Guster]

I'm *sort of* aware that many marks of all types were modified and upgraded through their time in service, and I was wondering if the descriptions apply to the variants in general or very specific variants modelled in the game?

 

For example the Ju-88 A-4 description says the plane's combat debut was in June 1941, but I believe, and correct me if I'm wrong, this variant was introduced in late 1940, after the A-1 and the A-5. Same with the Spit VB, where the info says winter 1941, but to my knowledge many squadrons reequipped with this during the spring of 1941, just slightly ahead of the 109 F-2.

 

It gets really confusing with the Soviet fighters, especially the Yaks, and so many online sources contradict each other, but I assume the in-game info refers to very specific variants, or possibly amalgamations of the most common features of the types within specific time frames. I understand there were often considerable differences between how the same plane was built at different plants.