First off we will be there during a time when it stays light to roughly 10pm.So why would they probably not make it to England?
Secondly we are walking along a path that is NOT on the roadway.
So I really don't expect to be walking in the dark or in areas where either the headlamp or warning strobe will be anything other than dead weight in the backpack.
But like I said, I will reserve that final decision for when we actually get the walking itinerary finalized. Here, where I walk/hike now, they are indispensable. Last evening I went out before dark but by the time I got back it was pitch black outside. There are no streetlights within a couple miles of where I live and the roads are just 2 lane roads. So I need these devices here. Doubt I will need them there.