Taking the parental control off again took over 3 hours for me.
Yesterday I tried BT Parental Controls ("light" plus a couple of other categories) and it seemed to work on the PC.
Today I found that the iPad could not connect as normal (tesco.com for example). Not understanding DNS and related matters in the online advice, I decided to keep things simple: I disabled BT Parental Controls. After "10 minutes" and a few resets the iPad was no better, so I decided to come back to it later. "Just wait longer" did actually work, and the iPad is back to normal.
I'll have to sort something else out before my granddaughter is allowed on our devices. Advice seems to go from "very simple" (go here to delete parental controls) to "assuming too much knowledge" (oblique references to OpenDNS and Google's 126.96.36.199 address).
So - whose blog should I be reading, I wonder? Or other source of advice? Suggestions welcome.