I think the only solution to your wireless schedule issue is to invest in a good third party router. Just check the specifications of anything you look at for the features you want. For example something like this.
From a FritzBox 3390. The new model is 3490 with AC wireless. Other makes no doubt have similar features.
My £35 TP Link router also has that facility, you can set a wireless schedule, or if you just want to block certain users, you can enable a block via the firewall at certain times, without stopping other users connecting.
This is the screen that shows this setting Disabling wireless during specific times
You will need to connected to BT Broadband to access this link, and any other links I post.
If you are connected To BT Broadband, and you cannot access the link, then please let me know. Thanks
Simply place the router on a timer socket!!
That will cause a nightly reset of the hub which is not a good idea as it will eventually probably affect your connection speed as the DLM takes action