Some details

All receive times were 30/60 min since you were logged in, and relogging/changing channels resets that.

I literally afked 4 hours for it and I got 8 fortune fees just as plannned lol.

I also have been getting them while afk. They do seem to conflict with the homestead event though. If your inventory is full they go into your temporary inventory with no time limit to reclaim. Once they do this they cancel any loaded skill such as fishing, thus making it impossible to afk fish for more than a couple hours without checking in.

Cheap trick to do both events at once: Get a Candy Jar in your inventory. Make every other open slot in your inventory 1x1, like a checkerboard. That way the Candy Jars will auto-stack, and the Fortune's Fees will fill all the open slots. The only things you can fish up that are 1x1 are the tiny fish that stack and potions.