I have been testing out the ability to promote External Client Apps through a pipeline. I found that if I include the 5 files (.eca, .ecaGlblOauth, .ecaOauthPlcy, .ecaOauth, and .ecaPlcy) that define the ECA, I receive an error of 'We couldn't update your OAuth Link...'.

But, if I edit the .ecaOauth file and remove the oauthLink tag/value then the promotion succeeds. This is an optional tag is set from the source org, and can be removed before promoting. It would be great if this was handled automatically, maybe with the problem analysis tool.