Hey GR rider,
I was checking the back end to see if there is a site wide time limit on editing posts (with images or no images) and it is set to 14400 minutes (or 10 days). If your posts (containing images) are beyond 10 days old, that is the reason you are not able to edit them.
By chance, are you attempting to edit your posts/images because of the photobucket issue or for another reason? Let us know and we'll go from there.