You have removed the option to quickly scroll from bottom to top by hold your finger on the scroller to the right (iOS) Please bring back! It takes forever to scroll through hundreds/thousands of pictures. Why have you recently removed a a lot of useable options?
Long press on the Scroll Handle, and the phone should give you haptic feedback indicating that it is in fast-scroll mode. Quickly scroll to the top or bottom.
The target is tiny, but you get used to it quickly.