CTS files - what are they and how to retrieve in my CT app

I have lost data recently using the HTTPS protococol, and I am trying to recover them using files in the data folder of my field unit (a Blackview). Long story short, I collected data, which I could see using the Options on my CT classic app, and at the end of the day I turned off and recherged my unit. Next day when I planned to send and download the data, the Send option indicated “No data” ! On my PC, the Download said “Nothing to download”. A situation that alas, has occurred a few times before, wasting my time and data.
I am desperate to recover those lost hours, so I looked for files on my unit and in the “Android\org.cybertracker.mobile.ct\files\cybertracker” I found several files including a *.CTS that is larger than the others (thus I assume it contains data).
I managed to convert files to a CTX before(through creation of a CAB file using the DAT and TXT files but never encountered a CTS file before. So,

  • What is that CTS file?
  • Is there a way to retrieve data from it?

The CTS file is just the application itself, so it does not contain data. All the data is in the .DAT file. The .WAY file is for the tracks.