Means of controlling the battery charge voltage limit on Bangle.js 2?

Over a period of 1h:11m:46s, starting from around 36% charge and an (almost certainly inaccurate) calculated battery voltage of 3.8126v, using that 67 mA-ish cut-off…

0.113 Ah (or 0.57442 Wh)

The USB power meter offers a way to calculate capacity, so by setting voltage to 3.8v and estimated charging efficiency to 90%, it results in an inaccurate estimated 0.1364 Ah battery capacity (real capacity is 350 mAh).

I attempted to calculate the voltage with the following (using the pc calculation to compare with the Bangle's own estimate):

let batteryFullVoltage = 0.3144;
let v = analogRead(D3);
let v = 4.2 * v / batteryFullVoltage;
if (v>=3.95) {
 let pc = 80 + (v-3.95)*20/(4.2-3.95); // 80%+
} else if (v>=3.7) {
 let pc = 10 + (v-3.7)*70/(3.95-3.7); // 10%+ is linear
} else {
 let pc = (v-3.3)*10/(3.7-3.3); // 0%+
}
Terminal.write("Batt voltage:" + (v).toFixed(4).toString() + "\n");

As it turns out, your estimate was pretty close! If I had drained the battery further, I'd probably have hit your target (I try to not let the battery dip too low, either).