2 years of photos gone from Camera Roll after iOS 11.1.1 update

Hi,

on my iPhone 6, after the minor iOS 11.1.1 update, a little more than 2 years of recent photos completely vanished from the iPhone's Camera Roll under Albums tab in the Photos app.

After the update, the newest photo currently in the Camera Roll is taken Sep 1st, 2015!

However - all my photos up until today are visible in the automated albums (Collections) when selecting the Photos tab and browsing the Year - Collections up until latest date.

So in a way, 2 years of photos are still there, but they are definitely gone from my Camera Roll. This also applies when trying to select Camera Roll photos from inside the common social media apps, the latest photo is definitely the one I took on Sep 1st, 2015.

Apart from the Camera Roll bringing back good memories from 2015 - is this 'feature' noted by anyone else?

I have backed up my iPhone numerous times to iTunes after the major iOS 11.1 update, however only the most recent (post-11.1.1) restore point is visible in iTunes, meaning that I can't revert to a recent state where the Camera Roll was intact. Or maybe i should try restoring to the most recent point and hope that the Camera Roll is repaired.

Thanks,

puklars