Refering to helpers in additional data of a schedule helper

Configuration
1

Now that it’s coming to winter I’m attempting to change how I’ve automated my heating to give easier configuration for each room
I’ve moved to using a schedule helper with just one schedule for the whole house (I may change this to a schedule per room but wanted to get this working first)
I’m configuring via the UI and using the advanced settings-additional data to set properties for the heating temperature for each room in each time block

for example on Monday 6-8am block there is additional data of
playroom_temperature: 19
that is then used in an automation to be controlling the relevant room’s trv
that’s working just fine

but what I want to do is to not have that hardcoded 19 and to have that refer to a number helper. something like:
playroom_temperature: '{{ states('input_number.playroom_auto_heating_target') | float }}'

the problem is, that that doesn’t work and I’ve tried a few different ways of expressing it.

Is it even possible to refer to other helpers in this way?

2

How does the automation look that actually sets the temperature like?
That could be modified to not just grab the number, but grab the string as a template.

3

i think that would limit the usefullness of the schedule as the automation would need to be able to grab different values depending on what time block it is in.
I currently have everything in automations executing scripts for the time blocks and it’s a bit unmanagable. I was thinking this should be a good use case for a schedule helper