Photostream in Photos Not Updating on MacBook Pro

Hardware:

MacBook Pro Retina

2.4GHz i5

8GB

OS X Yosemite 10.10.3

iPhone 6+ 128GB

iOS 8.3

Hope you can help. Please.

Updated to Photo on all my devices. All working fine until Saturday and now when I take a picture (or screen grab / save pic / etc) on my iPhone it no longer appears in Photo on my Mac.

They appear in my Photo stream on iCloud.com, but refuses to update on my MacBook. Photo stream is checked in the Preferences...

If I put the pic in a shared stream album it appears, but it doesn't appear in the 'Photos' or 'All Photos' section of Photo on the Mac.

I haven't changed any settings.

Any ideas?

Thanks in advance.

Dave