Extended holiday. Router/Modem on or off?

[#1]

Normally when I am away from home for a week I turn off all my IT equipment, including the Plusnet router but not the BT modem. I'm going to be away for closer to 3 weeks this year. Should I be doing anything different? Perhaps I should have been leaving the router on but I've not noticed any drop in speeds when everything is turned back on.

[#2]

If I am away for more than a few days I always turn all my equipment off including the router and BT modem and never have any problems when running them up again.

[#3]

Yes, you'd be fine to leave it off. Powering if on and off multiple times would eventually cause speeds to be lowered.