This is still happening to me as well. I have iOS 12.4.9 on an iPhone 6 with iNat app version 3.0.6. Sounds like the iphone 6 and anything below will not get iOS13 support in the future.
The photos all have the right data and will include accuracy when uploaded via the web, but will not include accuracy if using the phone app when images are pulled from photo library. If I use the in app camera feature the image will have accuracy data associated but not if you choose from the library.
Currently using batch edit afterward to add accuracy data back in.
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