Put some secret salt server side on weather generation so diggers won't know in advance using bm or other programs of their own when suprem is going to pop. So you'll have more challenge, less sup in your guild, and a game more fair.
Issue with sups is not that they are predictable. Its that you get them in one big lump and then nothing until next pop, ie. login, do the thing, and you can stay logout for X hours again.