Will It Update Old Posts?

I went ahead and installed it. It looks like it adds the info. However I tested it using the Structured Data Testing Tool and it’s showing errors for author, datepublished, headline, image, publisher, datemodified, and mainentityofpage. For all except the last two, it says a value is required (last two says “recommended”).

Any ideas? If needed, the page I tested was:

The link is: https://justplayinghouse.com/motherhood/parenting/mom-and-daughter-date-ideas