Possible to have more than IMG_9999?

There is no setting. Others have reported that an iPhone reaches IMG_9999 that it restarts at IMG_0001.

All cameras do this. When the image count reaches 9999 the next image will be 0001. The standard naming system for DCIM partitions on camera disks and, consequently, on iOS devices is to have 8 characters. Three are used by IMG, one for the underline and 4 for the number of images.

Your welcome!