I have a LOT of photos in my iCloud account...Over 100,000 actually (it is a combination of photos i took with my iPhone and ones that I took with my actual camera)....However, lately it keeps saying that it is 'Uploading 100,000' photos...then over the course of the day...the number it is says it is uploading gets smaller and smaller...then eventually it starts over to the over 100,000. It keeps doing this over and over..Also, when it does this my iPhone becomes really really sluggish and it eats up the battery much quicker than normal. Is there a trick to getting it to stop doing this cycle? I have tried turning off my iCloud photos account on my iPhone and turning it back on but it didn't help. On my iMac, however, it works normally. One thing I did do differently was i started up my old MacBook Pro which only uses Yosemite. Not sure if that would affect anything though...Also, for awhile i had the iOS 11 beta on my iPad as well, but now i reverted back to iOS 10 (i didn't update to iOS 11 on my iPhone though.)