I'm away from home and carrying on with some work which involves research on a range of websites. I'm using a BT FON connection but am being blocked from accessing certain sites by the parental controls on the router advertising FON.
I thought the FON VLAN was separate from the standard VLAN, either they are separate or they are not.
If you have BT's network parental controls enabled on your MyBT profile then the network level parental controls will also filter your FON (BTWifi) connection when out and about as well as your residential BT broadband connection.
I don't think the network level parental controls should filter your data packets if you are connected via BTWifi and have disabled the network level parental controls on your MyBT.
The BTWifi network uses a different subnet and virtual WAN connection to the residential connection.