It has to be a contiguous 24 hours, so no.
Correct, we really like to be connected for flex daily since it is so dynamic. If this is going to be an issue you can always use a fixed schedule which will not be affected by this requirement. You will lose any dynamic weather intelligence if the internet is down.
What about separate guest networks? Then you can disable them whenever you want for however long you want. That's how we do a lot of our testing.