Our current PR-validation CI pipeline has recently been converted to YAML. It needs some fixing up (paramaters in job templates is a bit nasty at the moment) but it works.

Our current full nightly build is NOT YAML based, and will break every time there is a CI update posted as a part of any feature/bugfix PR.

Convert the nightly rolling build to a YAML-based one, using the same templates as the PR-validation build so we only have to update CI processes in one place (if possible).