In a nutshell, U-Lyshak is a pretty fragmented land, ruled by local bickering lords around 4400. It is not until later that the kingdom of Helyssa is consolidated over much of the old crown-kingdom. Certainly the coasts are going to be raided by Ulor, and there will be some occupation as well. There might even be a few Ulor viceroys, as in Xa-ar
I hope to one day do a SW Jaiman module covering U-Lyshak and the mysterious Ly-Aran (to go along with Xa-ar in the NW, and Wuliris in the NE), but that's down the road.