Afterburners

Looking to lower fuel during ignition phase as getting a little too much flame when starting. won't be able to get plane out for a few days to try but while looking at the settings in the shop, I'm a little confused at the setting option. In the manual it says settings between 000 and 255 are possible yet mine was set for "AUTO +1" . I can lower to "AUTO + 0" and when lowering from that, it goes to 255 and then counts down by one incrementally with each button press. The manual doesn't explain what "AUTO + " is exactly. Anyone know where the "AUTO + 1" falls within the 000-255 or is it some type as the name implies an automatic setting that doesn't necessarily correspond to a predetermined number.