A release we did two days ago to an environment in Octopus from Azure DevOps Services using the name
SQL.ServerName.test that ran fine. That was using Octo.exe 5.2.6. Today it failed - and in the log I see that Azure’s now running Octo.exe v5.2.7.
The environment on Octopus is
SQL.ServerName.Test (upper case T on the domain suffix).
Changing the environment in Azure to match the case exactly fixed the issue.
Thinking such breaking changes should NOT be enforced without warning!