Today I noticed that we're still using the V4 blobs for Firefox Releases & Nightlies, even though we're up to V7. This hasn't been a problem so far, because most of the changes have been removing dead attributes (which we still set due to using the old blob, but Firefox ignores). However, we just added the new "backgroundInterval" attribute (https://bugzilla.mozilla.org/show_bug.cgi?id=1309660) that we're likely to need to use in the near future. This means that we should start submitting blobs new nightly & release blobs as V7. I _think_ the only thing we need to change in cli.py is to remove platformVersion from the submission - everything else we currently submit is still supported. https://github.com/mozilla/balrog/blob/master/auslib/blobs/apprelease.py has the full details on changes by blob version.

AFAIk, we're using version schema 9 now in balrgoworkers so I think this bug outlives its usefulness; do you agree we can close it?

Yes, I think this was fixed by https://bugzilla.mozilla.org/show_bug.cgi?id=1431789