"Marking dev + xenial as Invalid since it works from Xenial onward"
You marked trusty and dev as invalid, and kept xenial open? Unfortunately, there have been huge changes in the acquire system in 1.1, so there is likely no way to fix this in trusty.
"Marking dev + xenial as Invalid since it works from Xenial onward"
You marked trusty and dev as invalid, and kept xenial open? Unfortunately, there have been huge changes in the acquire system in 1.1, so there is likely no way to fix this in trusty.