It’s easy to fall asleep while the lights are on, or have the light turn-on in your kit. I know, back off the tail cap when packing your lights. 
When the led shuts down because of low voltage (when the voltage is below the Vf for a very small current), shouldn’t the led act like a resistor and pretty much stop the current? Is there a parallel path for current in the driver?
The MCU is in parallel with the LED. The 7135s are in series with the LED, but they also draw a small current via the MCU. Total current at that level is only a milliamp or two, but that’s still enough to kill an already-discharged cell within a few days.
I just bought 8 x S2+ SST20 7135x6 for Christmas gifts. I also bought the LED switch but wonder if they will override whatever LVP is built into these flashlights and destroy a non protected battery?
Biscotti should turn the flashlight off when battery is low
Still on gifts protected are a good choice as there is no need for high drain on this light
If what you’re referring to as “LED switch” is the lighted tailswitch (replacement button for Convoy S2), then it won’t work properly for Biscotti (the Convoy S2 SST20 uses Biscotti firmware by default). I think it would also be useful to print out copies of the Biscotti flowchart and text descriptions to include with the flashlight for gifting (since Convoy doesn’t include any printed instructions).
Thanks for the replies!