Our organization currently has an artifact feed per Team Project. We also have an organization-level feed that has our Team Project feeds set as upstream, as it makes the configuration of NuGet for various repositories in our organization much easier. If I have a package Foo in feed MyTeamProjectFeed, and that package is 2MB, but then I access it from feed MyOrganizationFeed which has MyTeamProjectFeed set as upstream, will I be billed for the 2MB of the original package (in MyTeamProjectFeed), or 4MB for the original package, plus the package that becomes cached (in MyOrganizationFeed)?
Yes, each copy of a package in Azure Artifacts counts towards your billing meter.