I’m pretty sure the 80% figure is based on the previous 3 years’ profits rather than whatever salary they pay themselves. I can only assume they‘re taking a post-dividend profit figure, whatever that’s called (retained earnings?)* I'm not an accountant * but as I understand it they pay themselves a small wage then take the dividend. I guess they'll get 80 percent of what they declare as their earnings. tbh they should count themselves fortunate if they get that. Presumably it will be at least 80 per cent of minimum wage. Still a lot better than the horrible pittances that are the universal credit and ssp.
or maybe as company owners they get nothing? Dunno.