Hi Spikey999 and gary101a
It may be that the hogs are visiting other parts of their ranges. The males have larger ranges than the females and the males are usually the first to return after hibernation. They may have come to you first, because you were providing food, but now they have fed up a bit, are exploring other parts of their ranges. Also other people may have begun to provide food. It’s also possible that some females are around now, so they may be using more time on courtship activities.
So fingers crossed they or some other hogs will turn up again soon.