for now PAF is the current customer.. and they want every single plane rolled out of CAC or PAC.
like I mentioned earlier, purchase of the planes is a delicate and complicated transaction and takes a long time. our Indian commentators seem to forget how long did it take their own country to finalize their MMRCA deal. so other potential customers of JF-17s cant be any different.
the fighter has made good enough appearances in the static and flight displays in major international air-shows including UK, Turkey, China and UAE. so the exposure is there, rest whatever happens in the form of negotiations and requirements is kept behind doors because no country wants its specifications broadcast to "all Internet gurus".
as far as the question or delayed or early sale of a new aircraft is concerned, well the countries that have bought Chinese planes in the past like F-7s dont need much convincing where JF-17 stands.