Trying to exclude: “-1000 - -70; 0 - 1000”. It only honors the positive exclusion. “1000 - -70” works. Its seems the range can’t start with a negative value.
With an exclusion set, switching classification methods sometimes sets the exclusion to “ 0-0” however the breaks tend to honor the original exclusion. Same problem with Jenks. Maybe this just has to do with the negative ranges. No issue with positive exclusions.
Applying an exclusion sets the method drop down to blank.
bug symbology
(sorry if you seen this before, I posted this in the under the less-than-ideal forum subgroup)
This is the type of thing that should get reported to Tech Support. They tend not to come to GeoNet looking for reported issues, but respond to documented cases as you have posted. It would be worth while zipping, shipping and hopefully they will investigate