ICC 800 wifi sequential zone programming howto

I don’t understand how to programm the following zones for sequential progression.
I would like for example this case:
Zone 1 : start 6PM, duration 20minutes
Zone 2, duration 15 minutes just after zone 1

How to configure zone 2 in that case ?

Please set the start time for zone 2 to 6:20 pm and the irrigation duration to 15 minutes.
Please refer to this article: