This is a worthwhile discussion. If it was the day after El Cap beta came out, that is an unrealistic expectation.
But the release comes out Sep 30th.
Some of us must run the El Cap Beta.
Others might be curious if L6 is ready or not.
Line6 needs to know they have an issue.
2 days after official El Cap for compatibility is 2 days too late. Some of us might use this stuff in a work situation and those that do not should not be left without working devices for released OSes for any amount of days.
Really there should be beta L6 software available weeks ago so we can try it out for them and let them know they are all set.
That's my $.02.