Yes, when the LVP warning level has been reached, it will blink 3 times at moderate speed, and output is reduced. If the critical level for LVP is reached when the output can't be reduced any longer, it will blink 8 times quickly and shut off the light, and then continue to run for 6 minutes, blinking the switch LED twice every 8 seconds.
In ramping, the output is reduced by 20% of the ramping level each time.
In mode set operation, it's reduced by 1 mode.
So for ramping, if it's at the max level of 150:
- first drop would be to level 120
- 2nd drop to level 96
- 3rd drop to level 76
- 4th drop to level 60
- 5th drop to level 48
- 6th drop to level 38
- 7th drop to level 30
- 8th drop to level 24
- 9th drop to level 19
- 10th drop to level 15
- 11th drop to level 12
- for the 12th drop when it gets below 10, it's dropped to level 1
So in ramping or modes sets, if it reaches the lowest output (level 1 or mode #1), then it monitors the battery for dropping below the critical level.
I don't see anything in the firmware that would allow you to return to the previous output level by a single click. Maybe this was discussed at some point but it's not how it ever worked in Narsil or NarsilM.
I do see a problem though with having to go thru 12 steps at a minimum of ~ 5 seconds each. Here's a breakdown of using other percentage drops:
25%: 150 -> 112 -> 84 -> 63 -> 47 -> 35 -> 26 -> 19 -> 14 -> 10.5 -> 1 (10 drops)
30%: 150 -> 105 -> 73 -> 51 -> 35 -> 24 -> 16 -> 11 -> 1 (8 drops)
32%: 150 -> 102 -> 69 -> 46 -> 31 -> 21 -> 14 -> 1 (7 drops)
35%: 150 -> 97 -> 63 -> 40 -> 26 -> 16 -> 10 -> 1 (7 drops)
36%: 150 -> 96 -> 61 -> 39 -> 24 -> 15 -> 1 (6 drops)
For the next version of NarsilM, I'd feel better going with 6 drops from max, using 36%.