Jo Shields Thanks for your reporting and investigating here. The change in version 0.3.12 is mainly for Jenkins proposal 202.
For using agents to upload files and passing limit credentials to agents, I choose SAS to upload blobs here. Sorry for missing the limit size for uploading each blob. It seems there are two choices here, one is still uploading large file on master using sdk or implementing uploading blocked blobs in this plugin.
Do you have update on this issue. I have bunch of file >>300MB and has been update since Jan 2019. The issue now is big file wasn't upload and the build was green so we didnt notice until today.