I found this very interesting looking card in HACS and want to give it some more 
visibility :
The included schedule-state-card.js card has an integrated visual editor, so we can change schedules using UI.
Edit: No, we can’t. It means the card editor, not a schedule editor.
Looks like a good idea for heating/trv automations.
The card is based on this project:
A custom component for Home Assistant that simplifies the creation of schedule-based automations.
It takes a very different approach from other projects of this type, because it only provides scheduling functionality. It does not try to replace the powerful automations framework that Home Assistant provides.
Instead, it separates the concepts of when you want something done, and what to do when that state arrives. Use schedule_state to handle the when, and standard Home Assistant tools to handle the what.
schedule_state allows you to create sensors that provide arbitrary values, based on the time of day and other criteria. Home Assistant can then use the state of these sensors to trigger other automations.