8 – Drupal image 404 error (via JSON:API)

My ‘gatsby develop’ command fails as image files (coming from Drupal 8) are returning a 404 error – I don’t understand why (this is new)

== Details: ==

JSON:API (which Gatsby uses to build the site), uses this URL:
https://dev-tuckel.pantheonsite.io/jsonapi/file/file

it provides this image URL:

https://dev-tuckel.pantheonsite.io/sites/default/files/2020-08/mckenzie%20falls.jpg

Which returns a 404. There are at least 3 other images that are returning a 404 error – this is strange.

== Investigation: ==

In: content> Files:
the file is 165.17 KB, which is strange, as I ussually upload higher quality images.

it also says it has 1 “use count”, however the “entity” field is empty (again, not usual)

I cleared the Admin > Performance cache (thinking it’s may a thumbnail / cache file error).

The site is hosted in the free dev tier of pantheon.

Prior: I was not working on Drupal at the time of failure, I was working on Gatsby code.

If you have any ideas, it would really help because I’m stumped.