Can I unplug the Full Fibre Openreach box from the mains electric.

[Stu28375]

Can I unplug the Full Fibre Openreach box from the mains electric. 
We had full fibre installed 5 days ago. All working fine. The installation engineer told us never to unplug the Openeeach box from the mains. 
We want to change the extension lead it's plugged into but this involves unplugging said box. 
Will this cause damage? Will we get our full fibre internet straight back?

If you can help I'd really appreciate it. 

[JimM1]

@Stu28375 No problem just switch it off, change your extension then plug it back in and switch it on, takes a couple of minutes to boot up to the 3 green lights then you hub will reconnect and off you go.

[Stu28375]

That's great. Thank you for your help.