Problem saving a SharePoint Site as a Project Online site template

Over the last year or so we have been having trouble saving any SharePoint site as a Project Online site template.  I had previously been able to save sites as templates in my various Project Online (government) tenants. 

Here's an example of what happens now when I try to create a basic project site and then save it as a template (which is the same error msg I get when I start with my existing project site template):

• Created a new subsite using the Project template
• 

   

• Then without doing anything else I tried to save it as a template
• 

   

• Got this error
• 

Has anyone else observed this problem?  Has anything changed in Project Online and/or SharePoint to cause this problem?  Any info would be helpful.

Thanks,

Jean