The VM Hub's routing facilities have also always been pretty basic. Many years ago I decided to facilitate what you want to do by getting my own wireless router with much better functionality. I was able to block out my 2 kids computers/phones/consoles etc at different times on different days of the week very successfuly.
If you want to do the same you will need to get your own wireless router with the functionality you want. Be aware that if the teens are tech savvy they will try anything to defeat your strategy - so you may have to do some savvy stuff. For example I photo'd the sticker on the Hub base so only I had the access passwords in the event of them trying to pinhole reset the Hub to bypass my router. Also ensure they cant guess you actual passwords
-------------------- John --------------------
My services: HD TV on VIP (+ Sky Sports & Movies & BT sport), x3 V6 boxes (1 wired 2 WiFi,) SH2 in modem mode with Airport Extreme Router. On VIVID200, Talk Anytime Phone, x2 Mobile SIM only iPhones.