With how STHS functions there is literally no way around it. Backups just go back to the last save so every game done between those saves needs to be re-done. If we could avoid it we would but unfortunately we can't.
I'm not saying you have to be happy about it, I'm saying that being angry isn't going to change anything because it isn't a choice, it's an unfortunate drawback we're stuck with. I asked Simon for a feature that would fix it but sadly got no response.