Issue using Lapse It Pro

I'm trying to use Lapse It Pro on a new Honor 7X by Huawei and I'm having issues with it cutting the time lapse off before it's supposed to. I've set it up three different times to capture frames for long periods and it's stopped after capturing images at about 3, 4, and 5.5 hours into filming. You can set how long the session goes from within the Lapse It app and it cuts things short every time, which makes me think it's possibly something outside the app that's causing it. Most recently I've set the 'Background Capture' option within the app to Fully enabled and this still didn't correct things. I bought this phone new to use just for this time lapse project and it isn't hooked up to my cell network. I've also tried setting the phone on airplane mode, with wi-fi off, and it still happens.

Any idea what's going on here?