DisturbPlease cydia tweak enhances Do Not Disturb mode by allowing you to get SMS/MMS/iMessage notifications for a selected group of contacts while DnD is active.
Messages from contacts belonging to that group will play normal alerts (sound alert, and screen will turn on), even during DnD mode. You can choose to have audible notifications for messages from anyone, no-one (default in iOS), your Favorites, all people from your contact list or just from people belonging to a custom group of contacts – same as in incoming calls DnD settings.
You can also choose the weekdays when scheduled DnD will be enabled or disabled (in stock iOS all weekdays are enabled, and you cannot choose on which days it should be enabled or disabled). If you disable scheduled DnD start for a certain weekday, your device will not enter DnD mode at the scheduled time, but it will still exit DnD mode automatically when DnD is scheduled to end (if you have manually enabled it in the meantime).
Custom settings are integrated into Settings/Do Not Disturb (marked with ‘Powered by DisturbPlease’), and advanced settings are available in Settings/DisturbPlease.