WTH Icharger? Why won't an iCharger 308 discharge over 10.5-11.0 Amps?

Yes, the 308 will discharge at 11 amps without a resistor bank. If you want to go higher, then watch this video:

Because you did not read the manual?
https://cdn.shopify.com/s/files/1/03...8DuoManual.pdf
page 39

The charger itself can only handle an amount of discharge power, by using an external resistor you can go higer.

Well that's interesting. It's been fine for a couple years, 20 amp cycles, no trouble...

Were you cycling a 1S battery when achieving 20 amps? (guess based on picture). Per the 80 watts internal discharge power rating 20A should be doable on a 1S. With a 2S pack it's limited to essentially half of the current it can do on a 1S. Need an external resistor setup as mentioned, or a regenerative setup with extra batteries, basically discharge on one port of the charger while charging on the other port.