Can you only have saves from two characters at the same time or did my main campaign 20 hrs in get scrubbed by a bug? Made a 3rd character and played through the introduction area so I had next playthrough ready to go, got no warning when starting that "this will scrub your oldes characters save files" so more leaning to believe it is a bug that removed my saves?

In the game options you can specify the maximum number of quicksaves and autosaves, 3 by default. If you made a manual save and it was lost, then it may be a bug.

Edit: It also will not distinguish two characters with the same name and treats them as one character for the purpose of save sorting, though the saves will still be there.

Meant not how many auto/quick saves, meant how many games you can have running as in one game you play a paladin and at the same time you might have a fighter going that is at another part of the game, I had 2 different games going and when I made a 3rd new game it deleted one of the other games I had going, ofc the highest level game.

I have 3 different games at the moment, though two are from game version 1.02 and all have manual saves, and haven't had any of them disappear. I only mentioned the quick/autosave limit because that limit is across all your games, so if one game used only quicksaves it would be lost once you quicksaved enough times in a different playthrough.

All over, sounds like a bug.
Out of curiousity: Are you using 1 single save per "game" you're playing?

Nope, I have like twenty on my current game and maybe 5 on each of the others.

You do need to manually save if you want to change characters, the autosave and quicksave slots are -not- character dependent.

Oh wow, thanks that explains it then, thats horrible cause don´t think I have seen any warnings of that. :-/ 20-30 hrs playtime down the drain, luckily I were not super happy with my build so just started a more optimized character of that build now and just bulldoze through to the point I were at with story mode difficulty so I catch up fast to where I were. ^^

Which is utterly stupid. Other games do it, why not Kingmaker? [\Rhetorical question]

If you use GOG Galaxy and cloud saves, you can download a backup of your older saves from the cloud to manually restore them.