Question: lost photos
I have an iPhone 5S which last night updated to ios 11.2.6 and it also completed a back up to my iCloud.
However, I have noticed this evening that all by 50 of my photos (1000s) have disappeared from my phone but I can see them all on the iCloud (logging into iCloud via a Web browser).
I presume that if I allow my phone to complete another backup, it will backup merely what is on the phone (58 photos). Am I therefore at risk of the backup of my 9000 odd photos on iCloud being deleted?
I have previously downloaded the content of my iCloud to a folder I setup on my PC to have a copy of my photos independent of the iCloud app. I have tried to download photos since that last manual download but when accessing the iCloud (via a web browser) it is not possible (seemingly) to select more than 1 photo at a time.
How can these problems be resolved please?
iPhone 5s, iOS 11.2.6