Originally Posted by
404yxl
Reserve is 100% considered duty under 117.
Duty means any task that a flightcrew member performs as required by the certificate holder
No rest period is required because you aren't performing a FDP and long call also requires at least 10 hours of rest before performing any FDP. You could do office work for 1000 straight hours, but until you go on prospective rest and receive at least 30 hours of rest in the previous 168 hours, you won't be performing any FDP.
The language is a mess. You're on "duty" because you're required to perform a task (answer the phone) but you're not on Flight Duty because you're only in a reserve availability period. 117 allows for some of this to count, but not all of that, and etc. etc. etc.
I'm going to have to crawl back in my hole and study this (and the beer rules) apparently as I've only gotten myself confused again.
Thanks to all for clearing the cobwebs out!