You can create a group policy to allow access to torrent sites (and another policy to block), change the SSiD firewall settings to allow/block L7 rules for Peer to Peer access. You can turn on SSiD's using SSiD availability and time bands. But, I don't think you can do both other then having one SSiD available at certain times (which allows torrents), this then turns off and a different SSiD that blocks torrents comes on line when the other goes off within the dashboard itself...
You could run API script(s) to move the clients from the allowed (P2P) policy to a block policy at different times of the day (and then back again), that way the policies would apply to a single SSiD and I think this would do want you want it to do
@MichelRueger Yes, good call, I missed the schedule option, but I don't think that'll do what you need as the client can only be in one group policy at a time, so if they try to access the internet when the time schedule is set to off (for the policy they have been assigned), they won't get any access, as the schedule is off.
You need to be able to toggle clints between 2 different policies,....Sadly, I think API scripts is the only way to be able to do that
Scrub above, testing shows that when the time schedule is off for the policy (i.e. that allows P2P) then the client is assigned 'normal' access (no policy) and the default settings (i.e. no P2P) for the SSiD is applied, so @MichelRueger , yes your solution will work