To confirm, I'm still seeing this problem. Something within PL/SQL Dev appears to be caching results, even when 'check now' is used.

Where on the site can we check for updated versions?

You can always go here.

But Marco that page lists two versions =- 10.0.0 and 10.0.2 .
I'm running 10.0.2.1697 which isn't listed on the page.

Again, how can I check if there are any updates available?

I don't see 10.0.0 available for download there, only 10.0.2, which is the latest version.

The 10.0.2 version is the one you have. The build number is not significant.

That page lists 10.0.3, but the updates page used by the app (http://www.allroundautomations.com/update/pls.updates) doesn't?

The update has indeed not yet been published through the on-line update system. This will be done shortly.