Thanks for your explanation
GoogleFrog, tho I see the need to clarify it since the issue isn't quite about the behavior after updates or playing new maps. What I meant by "game" was matches, not the program. I meant, the first match loaded after each launch of the program took really long time, regardless of updates. As I said I have to "spectate a game" to give it time to load. After that it loads normally.
For a little more context I noticed this issue only in recent months. Pretty sure it wasn't like that last year.
Btw, might be related, the game will create a folder named "a" at the root directory of my HDD. Why is that the case and is it really necessary?