Instant Upload not reliable at all. Failure to upload all photos

Took a series of 6 photos while outside. Of course, the app complains I’ve got no Internet connexion and output multiple failures to upload the photos instantly. I don’t use mobile Internet while on the go (and I guess Nextcloud devs took account of this possibililty, e.g. in Belgium, mobile Internet is really really expensive). Once arrived at home, I turn on the Wi-Fi on my Pixel. Unfortunately, Nextcloud app only uploaded last 2 photos out of 6. So, my question, is it possible to improve the Nextcloud app so that it does not complain when no network connexion and that it waits patiently until I have again an Internet connexion. Also, is it possible, that Nextcloud app upload all the 6 photos I took and not only the last two ones. It seems to me, after personal use and some experiments, that the instant upload feature is not reliable. From what I have read, this is a recurring issue. As a simple user, I only wanted to raise this issue so that someday, sometime, in the near or far future, a dev will look into it.

Thank you.

Nextcloud app version: 3.28.9 on Android 14/Pixel.

UPDATE
Apparently, it uploaded all the 6 photos, but took a lot of time before uploading the first 4. So, my new question is: is it possible the app swiftly detects when the Android successfully connects to a Wi-Fi hotspot, then uploads all photos in one go, and not partially?

Again, would be nice if the app does not fall in tears when not Internet connexion.

Do you have Only upload on unmetered WiFi enabled on each of your auto-upload profiles?