Message started appearing in OSX jobs:

The macOS-10.15 environment is deprecated, consider switching to macos-11(macos-latest),
macos-12 instead. For more details see https://github.com/actions/virtual-environments/issues/5583

Quoting from the upstream issue:

Deprecation will begin on 5/31/2022 and the image will be fully unsupported by 8/30/2022

To raise awareness of the upcoming removal, we will temporarily fail jobs using macOS 10.15. Builds that are scheduled to run during the brownout periods will fail. The brownouts are scheduled for the following dates and times:

GitHub Actions:

• July 21, 12:00 UTC - July 22, 18:00 UTC
• July 27, 00:00 UTC - July 28, 00:00 UTC
• August 3, 00:00 UTC - August 4, 00:00 UTC
• August 15, 00:00 UTC - August 16, 00:00 UTC
• August 26, 00:00 UTC - August 27, 00:00 UTC
• August 29, 00:00 UTC - August 30, 00:00 UTC

Azure DevOps

• August 1, 12:00 UTC - August 1, 14:00 UTC
• August 9, 16:00 UTC - August 9, 18:00 UTC
• August 17, 14:00 UTC - August 17, 18:00 UTC
• August 25, 14:00 UTC - August 25, 20:00 UTC
• September 2, 12:00 UTC - September 2, 22:00 UTC
• September 8, 00:00 UTC - September 9, 00:00 UTC
• September 14, 00:00 UTC - September 15, 00:00 UTC
• September 20, 00:00 UTC - September 21, 00:00 UTC
• September 26, 00:00 UTC - September 27, 00:00 UTC

Those brownouts get pretty extensive - 24h for all but the first on GHA, and the same a bit later on Azure - so it sounds we need to move until end of July with this.