That does sound really odd. My first thought was to un-sync and re-sync but you did that already. Maybe create a new collection for just the Photoshop edits. Move those files to the new collection, and then sync it.
The only other thought is that maybe the metadata for the edited file isn't synced with Lightroom. The image would have an icon in the upper right with an exclamation mark. I doubt this is the problem though, because you said that the edits show up in Lightroom, just not the synced version online.
I haven't tried syncing any Photoshop files yet. I'll have to give it a try and see if it works for me.
I did try a separate collection but that didn't help and metadata is all up to date, as you mention this is partly confirmed buy the correct preview in Lightroom.
I did try removing it from the stack too but still no change.
I have another idea. It's just a guess. Log into your LR Mobile account through a browser. The easiest way to do this is through adobe.com. Go there first. Make sure you are logged into your account, then click on the LR icon in the panel on the left. Now find the images that won't preview correctly, and delete them. Hopefully this will force Lightroom to re-sync the images, and create a new preview.
I'm thinking that the edit tiff gets created immediately when you go from LR to PS. If you are starting from a synced collection, the edit file is also immediately synced. LR Mobile may be having a hard time syncing the PS edits because they are made in PS not LR. Like I said it's just a guess though.
Ok, I gave this a try and it did work. I deleted the photo online and then put it back in the synced collection in Lightroom and when it appeared online it was showing the updated PSD.
I then tried making an obvious edit (changed to B&W) to the PSD in Photoshop and when it finished saving the preview in Lightroom updated, and then it started re-syncing, however the online file remained the same. Converting the file to B&W in Lightroom also triggers a re-sync which reflected online.
So it looks like Lightroom is trying to sync the changes made in Photoshop but they're not showing on the site.
It sounds like the Photoshop edit can not trigger a new creation of the preview jpeg in the online gallery. It kind of makes sense to me that this would happen because the edit is coming from Photoshop, not Lightroom. The desktop LR is updating it's preview but it is not pushing this update out online. When I get a chance I will play with it on my system and let you know if I get the same results.
Hi Theresa, did you get any further with this?
It worked for me. I synced some Photoshop files to Lightroom mobile. Then I edited one of the PSD files in Photoshop by adding a black and white adjustment layer. It updated immediately in LR, but took a little longer to update online. First I was viewing the public link which was not showing the PS edit. I switched to the private link which did show the black and white version. When I returned to the public link the image had switched to b&w.
I'm not sure what to tell you because I can't duplicate what you are seeing.
I shall continue messing around and see if I can recreate it reliably. Thanks for your time on this.