I suppose, but I still find the inconsistency confusing. Some things autosaving and others requiring manual action to save (all in the same popup) is a bit weird to me. Not a big deal, I just thought it worked differently before and got confused. Could just be misremembering though.
I think what’s confusing to me is that there are several options that are given, but then it is always saved as custom. I suppose at a certain point those presets are just there to help you, and always saving it on the backend as a datetime makes sense, but then I wouldn’t expect clicking the presets to save and close the popup. I’d expect the calendar to be the most prominent part of the popup, with smaller “helper” buttons to automatically update the calendar to those presets, but not autosave. Reading your response and thinking about it more does make this feel more like a UX suggestion than a bug though.