Time zone changes affect file names in Camera Uploads (iOS)

I’m currently working and living in different countries in different time zones (one-hour difference). During my work trips, I take hundreds of photos of archival documents and other research materials on my iPhone. I’ve set the photos to back up automatically through Camera Uploads according to date of creation, in order to maintain the original chronological order. If (and often when) Camera Uploads isn’t able to upload all new photos while I’m still in my country of work, I finish the process once I’m back home.

However, I recently discovered that Camera Uploads nowadays changes the timestamp in the file name to reflect the time zone of the _upload_ location, which in my case means adding an hour to the original/local time of creation. In addition, since Camera Uploads seemingly doesn’t follow any chronological or logical order in uploading files, the incorrect timestamp occurs at random intervals, thus affecting both older and newer photos in a batch of ~1,000. In other words, my photos are now in a completely scrambled order.

This is EXTREMELY problematic as I use photos to document the exact structure and nomenclature of the archives from which I’m gathering materials. So not only do I not know which photos form a whole (e.g., a document, the contents of a folder...), but worse still, I’m also not sure which archival entity they belong to, which means I cannot cite them appropriately.

Luckily, sorting according to ‘date taken’ in Windows File Explorer helps me locate the incorrect file names. However, these kinds of manual workarounds are always prone to mistakes, not to mention frustrating and time-consuming. It would help if I at least knew which photos were uploaded to Dropbox in the new time zone, but the only date type Dropbox seems to offer is ‘date modified’ (original timestamp + 1h, so correct chronological order).

So that this never ever happens again in the future: how can I set Camera Uploads to preserve the _ORIGINAL_ timestamp, regardless of the time zone during upload (or any other external factor, for that matter)? This hassle is infuriatingly unnecessary – I don’t remember this ever being a problem earlier. I’m reluctant to set my time zone to either country manually in my Dropbox settings, as that messes up the timestamp of some other things. But is it the only option?