That's what I'm going to do eventually... Raspberry Pi to trigger them simultaneously, but until I have that up and running (will take some time), I was hoping to just go with the schedule feature....

My apologies, the firmware version that is installed is actually 1.1.3, I've updated the original post. That was my first idea, too, but didn't solve the problem.

Model : Hardware Version : Firmware Version : ISP : Model : HS100(EU) Hardware Version : 1.0 Firmware Version : 1.1.3 ISP : idk I have 3 HS100 smart plugs that need to be coordinated at the same time...