Well judging by the amount of people asking for saves I am not the only one. I just checked and that is infact what happened maybe I didn't have the space to copy the saves and instead they just deleted them.
I ran the previous version to check and all of them are gone.
I am unfamiliar with how Unity programs preserve saves, but I can tell you one thing, no download of any program copies saves from anywhere. Nor do they contain your previous saves. Nor does extracting a zip file execute any code whatsoever.
There is a location on your computer where saves are stored. The program goes to that location to get your previous saves (and stores them there when you make new ones). I have seen problems occur where mods are used, or where the links on F95 comes from a different upload platform (i.e SubscribeStar one time and Patreon another).
I can be specific as to where this game's saves are currently stored. On my Windows system, they can be found at:
c:/Users/<my username>/AppData/Local/VNGINE/Timestamps Lost Love
So, unless you have deleted them, they should still be there.
I know that in Ren'Py, saves are stored in two places, within the downloaded game's folder itself, and in the program's designated save location. Perhaps Unity only uses the one place, since if there is a save location with the game, I don't recognize it.