Giant Explore E+ 3 GTS

Just picked up a 2018 Giant Explore and have a few questions:

What does the “GTS” stand for? I see other product listings for 2018 without this description. Could it be because I have a late model 2018 with 5 pedal assist modes (see photo)?

Also, there is a sticker on the seat tube that says Giant with a big number 3 (see photo). Is this because it is an Explore 3? Hopefully this won’t get confused with Class 3 as I don’t see where the bike is marked anywhere else and I know it is a Class 1 bike.

I am also getting good mileage out of the 400 Wh battery so far. I was concerned about the battery size initially, but I am finishing my hilly rides with 60%+ battery or more remaining. I mainly ride on Eco or Eco+. I have been re-charging with this much charge remaining. Is this OK on the battery? Or should I discharge it more before charging?

I also have several long downhill stretches on my rides where I am typically braking or pedaling lightly. Is there any benefit to setting the pedal assist at “Off” during these stretches?

Thanks in advance for your information and guidance.