Simon 5 is coming soon!
Simon version 5 is currently in beta testing. It is a massive update, introducing a much-requested feature: syncing the Simon data between multiple Macs, plus a Simon Status service, a Link Checker filter, improved Find filter, iMessage and Speak Error notifiers, a new app icon, and much more.
Important: please note that Simon 5 requires a minimum of macOS 10.12 (Sierra), and will be a paid upgrade from Simon 4 after the beta. Purchasers since September 1, 2020 automatically get a version 5 license (that also works in previous versions).
Re: What does this mean? "Simon license with up to 15 active ...
It means you can only run up to 15 tests at once.
Re: What does this mean? "Simon license with up to 15 active ...
A test configuration is a line in the tests table, i.e. a website or server to check. You add them via the New Test command.
Simon only counts tests that are not paused against your limit. So if you have 20 tests, but 5 of them are paused, that means that only 15 are active, and so you'd be within the 15-test limit for a Bronze license.
I say "test configuration" to make it clearer that I'm not talking about checks — each test can be checked an unlimited amount of times.