hi, iPhone 3G S here... this bug may be an apple bug, but it's on timelapse that I have noticed it...
when setting numbers using the scroll method (eg: "stop after..." screens, if multiple wheels are scrolled after each other (multiple sequential single-finger-swipes), then only the last wheel to stop turning is registered as changing.
eg: if "After 1 photo" is selected, and I quickly swipe the thousands, then hundreds columns to read '9901', the thousands column finishes scrolling and does not register, and I end up with 'After 901 Photos' once the hundreds column finishes scrolling.
I can replicate this in the hours/min/sec option as well, but not in the 'on date/hour' option.
I can post screenshots if this is not clear.