Can't get Input Date/Time Entities Into Calendar

I’ve been tracking various maintenance dates with Input Booleans and Date/Time Inputs. This has been working fine but I’m ready for something more mature:

I’ve tried putting these input date/times in the calendar card and it doesn’t work because they’re not calendar entities

OK, I get that and I found Entities Calendar - turn your entities into a calendar. I put that in to build a calendar of my maintenance items and I put THAT into the calendar. It works but its not actually using the date of the input, it’s tracking the timestamp of when the entities last changed. Needless to say, the entities are jumping all over the calendar regardless of the date in the input date/time every time I restart.

I’ve read a dozen threads and they all seem to illude that this is not possible inside HA without some other calendar integration. For my situation, with HA calculating dates, another calendar integration just to feed it into the calendar card seems redundant.

I MUST be doing something wrong or not understanding something. Is there a way to get input date/times to display in the calendar card?

This initial release only really supports sensors with a device_class of “timestamp”.
These will create all-day calendar events using the state of the sensor as the date.

Other entity types can be used, but these will create all-day events based on the last_changed attribute.
Support for other types of sensors (and for events which are not all-day) may be added in future releases.

Looks like it hasn’t fully been implemented yet…

I remember reading that and I guess it didn’t really sink in as to what that meant until you pointed it out and I tried to create another input boolean. It’s very clearly not a timestamp device class. That’s my mistake and certainly explains my issues.

I can probably make the 2nd suggestion work if I do some rewiring of supporting processes. When I was on hubitat, I was only tracking the last changed date but then in HA, I learned how to do time calculations based off the last changed and THAT is the reflection of the date in my inputs. So if I take my time calculations out of the automations, go back to tracking last state change, then on the calendar add an offset for the future date calculation (usually 15/30/60/120/180 days out), I should be able to make this work.

Thanks for confirming I’m not missing some obvious functionality.