What is the original time interval for AFL code using multiple time frames?

The 2 links below made references to the original time interval.

What is the original time interval in the context of writing AFL code that handle multiple time frames? Is it the base time interval configured in File->database settings? Or is it daily by default?

When it is mentioned switching/getting "back to original interval" then original selected chart interval of toolbar or set periodicity of analysis settings are meant. The compressed interval of timeframe functions has to be a multiple of that original interval. You can not switch to 1minute from selected (original) hourly chart interval, for example. But you can switch to 2hour, 3hour 4hour,..., daily (->24h) etc.