How far, how much climbing and how long will my ebike battery last?

Barrie's been keen ever since I got the ebike to see how much we could get out the battery, or actually to see if he could manage to drain it completely and make me cycle a very heavy bicycle with no electrical assistance. So on Saturday morning we set off to discover if it could manage to do the climb to the top of Glentress then cycle to Innerleithen, bike up to Minch Moor and round the cross country track there and return to Peebles on a single 500W battery.
My theory was if I did as much possible in the lowest mode (eco) I'd manage to preserve as much life as possible and avoid the dreaded un-assist bike back to the car!

One of the steepest climbs at Glentress and I scooted ahead to save time and power and enjoyed seeing Barrie struggle up on manual power!

Time for a quick worried looking selfie at the mast at the top of Glentress and I was 2 bars out of 5 energy bars down on the ebike display!

Most of the trip to Innerleithen was downhill so very little battery energy was used up on the journey, this was a luxurious country house we biked past which has been converted into a retreat for the ultra rich. Don't think we'll be spending a holiday here somehow....

Another enjoyable moment for me watching Barrie struggle up another steep climb, this time on the way up to Minch Moor!

We reached the summit at Innerleithe and I was down to 2 bars left on the display but at least on the descent back down I wouldn't  use too much ebike energy up so by the time we got back down for the ride along the side of the River Tweed to Peebles I still had one bar left and felt confident enough to enjoy the final 6 miles into a headwind on a higher assistance mode! 

We managed nearly 35 miles and over 4000 feet of climbing with probably about another 5ish miles left in the battery, an interesting experiment and good to know what the ebike's capable of.