I have a a number of aerial photography and historic mapping layers which cached image services. These need to be added to a webmap with a bunch of dynamic services. I would like to group them (ie all aerials together) to keep the map tidy but I am aware there is no functionality in AGOL web maps to have group layers. Is there another way to do this? f not, I will have to not hold them as cached services, which would be detrimental for performance.