iPhone notification when wifi network changes

This is for a tweak, so the target is jailbroken devices, and not the app store. I have tried hooking different methods in the SBWiFiManager but they either are called when the wifi strength changes (so continuously) or after quite delay after the network has changed.

Is there any other way to get a notification (or another method to hook) went the wifi network changes?

I know you can get the current SSID with public APIs now, but I need to be told when it changes.