my understanding:
The latest firmware is referred to as 2v0 or 2.0. The firmware is different from the driver software for Windows PC, which the lastest is version 3.26.
After flashing the 2v0 firmware, (in Windows) the LHLabs control panel app will show firmware version 2.0 installed. The control panel app will also show the driver version in use on your windows PC.
If you check the firmware version number on your Pulse unit itself, it will say "Main 3.0" and "MCU 2.4", at least that is for my Pulse.
So, the 2v0 firmware file is the latest, and after flashing the Pulse with it, the Pulse will report Main 3.0 on its on-unit display.
If you have the previous 1v5 firmware, the Pulse unit will report Main 2.0 on its on-unit display.