It’s great that you have a different pipeline for each case! But we don’t have a naming convention, so you still need to change the buildkite-agent pipeline upload command for each one of them.
buildkite-agent pipeline upload [file] [options...] allows you to change the pipeline of a running build by uploading a YML configuration file. If no configuration file is provided, the command looks for the file in the following locations:
buildkite.yml
buildkite.yaml
buildkite.json
.buildkite/pipeline.yml
.buildkite/pipeline.yaml
.buildkite/pipeline.json
buildkite/pipeline.yml
buildkite/pipeline.yaml
buildkite/pipeline.json
You can also pipe build pipelines to the command allowing you to create scripts that generate dynamic pipelines.
There are two options where to store the configuration files: within your repository, or in Buildkite. For the last case, you can use the YAML steps.
You can read a bit more about customizing the pipeline upload path in here.