I want to achieve following on the google spreadsheet :
Let's say I want some of my cells to take the value of another cell at specific dates and times.
The value is actually just a background color, but if that's a problem, it could be some text, even if I prefer the background color.
For example in this sheet : https://docs.google.com/spreadsheets/d/15icn5bi-wZY1HZeLwpoM2Z_XrKOqydUH1BgdDGEEqLM/edit?usp=sharing
Let's say I want my cells A3, A5 and A6 to become like the cell F1 every monday, wednesday and friday at 6:30 am GMT+1.
Then the user can modify it but every Monday, Wednesday and Friday at 6:30 am GMT+1 the value is reset to the value of F1.