We are please to announce that an Advanced Weekly Scheduler module for Mango that supports override and exception days is coming out soon. It is currently available as beta for anyone that wants to test it.
There is still work being done on the UI but here is a sneak peak of how it works:
If you want to test this out you can install it into your Mango by first going to System Settings and changing your "Upgrade release channel" to Beta.
Then go to the Modules page and click "Check for updates" be sure to update any other modules and core to the latest.
There will be more updates coming out soon and a production release shortly.