Image posting guidelines - multple images

Please explain the following part of the guidelines and give me an example or two to demonstrate exactly what it means:
"For demonstrative purposes additional re-posts containing derivatives of the same image are also allowed - up to 4 re-posts per topic. Multiple "related" images or themes may also be posted - but only when they are combined into one final image file and they adhere to the sizing requirements below."

For example, is it possible to post a multiple image sequence of an eagle stealing a fish from an osprey. If so, exactly how could it be done? Would they be considered derivatives of the same image? If so how would they be posted? Or would they be considered related images? If so how would you combine, say 5 or 6 images into one final file and still adhere to the sizing requirements?

This portion of the guidelines seems really unclear to me.
Bob

Examples of derivatives of the same image would include different crops of the same original image file, or different processing adjustments of the same original image, or a color + B&W treatment of the same original image. The operative phrase here is "same image". These are considered reposts and as the guidelines state, up to 4 of them per critique post are acceptable.

Related image or themes would be anything else not derived from the same original image. The purpose of the critique threads generally is to present and comment on a single image rather than multiple images. If multiple images are to be presented, they should be posted in separate threads per the timing guidelines (one post every 24 hours in most forums). But sometimes there's an interest in showing a sequence like you describe, or perhaps a time lapse series of a moon eclipse, or whatever. These can be combined into a single image file either as a collage of tiled images (each of which would be small), or by overlaying & stacking the images to show the action as with a multiple exposure...