The way I think it works is if the Car / Tesla app is set to ‘Off-peak’ charge it wont automatically start charging when you plug-in during the evening.
Then Octo sets the schedule and when ready triggers the charge, at which point the car does what it is told.
Now maybe the car wouldn’t charge after 0530 (not had this scenario since I made the setting), but I suspect it would do what it is told.
It is being given a command to charge, just like when you click ‘start charging’ yourself in the tesla app.
Here are my Tesla app ‘Schedule’ settings and the charge I received last night (shown in Tessie app).
View attachment 859779
You can ignore the departure/precondition settings. Just enable off-peak, all week, and set 0530 as the end time.
Charge events last night:
View attachment 859780
I’ll let you know if I don’t ever make the 80% target in the car by 0700.