Unable to import assets when Substance file located on network location

My normal workflow has always been to store my project on a network location. The network storage is a local network not cloud based. Previously I have been able to import assets (fbx, png, spsm, etc) to the project with no issue.

However recently I have noticed that it consistently fails to import if the source file resides on a network location, even if the network location is the same as the Substance file.

If I relocate the file to be imported to a local drive, leaving the Substance file on the network location, then the import succeeds. Has there been a change in behaviour of imports?