iCloud Drive sync does not trigger Folder Action

This is a strange and probably slightly convoluted issue and I'm wondering if anybody else has experienced the same thing?

Running Mac OS 10.13.3 with iCloud Drive enabled and documents folder stored in iCloud, I have a Folder Action set up on a sub-folder to run whenever a change occurs in that folder. Folder Action is enabled on the folder and a script set to run.

If I upload a file to that folder from my iOS device (via the Files application on there, or using an application which writes to the folder), the file is synced on my MacBook with no problem but the folder action does not run. If I use the Files application on my iOS device to edit the filename and save that change, the edit is reflected on my MacBook and the folder action DOES run.

I've looked and I can't find any existing issue where folder actions do not run with iCloud documents. Has anybody else experienced this?