So I had the exact same thing as you have, when I set mine up. You can go above 120.....but have to do it with a laptop. I have mine at 134 and 148 and that's where I got full travel. I usually like them closer together, but I got tired of adjusting the tail control rod. I think I was right around where any adjustment and then it would go the other way. I settled here, and been flying it since.
Now, do you need it, no. It will be fine right where you have it. I don't know why it's that way, as none of my other models are like this, and it's the exact same setup, same parts, same servo Futaba BLS276, with a Neo. I did go bigger than 16.5mm......I can't recall off the top of my head how far out I went, but I too, went too far and the push rod hit the boom clamp. I think I'm some where around the 18.5-19mm range.
Here's a quick vid I shot showing my tail throws and my range of travel. It can be done, just done a little differently than how you would do other models.
https://www.youtube.com/watch?v=ZEtAU7Fx-fw