I agree with the others that pigs have no problem with getting fed at irregular times or in the dark. Only problem we had was with some GOS boars, about 4 months old, who got so excited at feed time and, perhaps couldn't see the electric fencing in the dark,would often charge through the damn Fencing!!! Then I would have 2 hungry pigs hassling me in the dark near the food bins!
This winter was hard though, me and my hubby work full time with early starts, so were doing morning and evening feeds in the dark. When it came to the weekend, the pigs had to wait while we had a lie in!