It is not clear where the <address> element can still be contained? According to the HTML5 specification https://www.w3.org/TR/html5/sections.html#the-article-element
Where the content flow is expected.
Approximate translation: Between the flow content tags.
But if you read further, it is written
Body address or body element ancestor
Approximate translation: The <address> element represents the contents of the nearest <article> or <body> parent element
Therefore, it is unclear whether the element can be contained between the <article> and <body> or between the flow content , where are a bunch of tags?
<article>, then this is the contact information for this article. If inside<body>(ie, outside<article>, if they are there), then for the whole document / page. - Visman