Hi there,
I reached out to SEOPress, and they said it’s something handled by the site theme.
To cover: %%post_excerpt%% is a variable that is registered with the SEO Press plugin.
Presumably that string is replaced with the excerpt via a function of the SEO Press plugin.
If that function was returning the same excerpt that the theme outputs then it would not have the caption ( you can see that in the post archives, or rather you can’t see the caption 🙂 )
I had a look at their documentation and i did find this:
https://www.seopress.org/support/hooks/filter-excerpt-length-metas/
Which is filter that looks and sounds like it is setting their excerpt length. Which means they must have a function that is getting their excerpt.
So… Can you ask them how exactly it is related to the theme?
If theres something we can do then let us know 🙂