they can do fine without dry food for quite some time... if you are unsure about the new stuff, I wouldnt give it to them until you get the time to buy their usual food.
Dry food isnt that good anyway, as it gets soft in their mouth so quickly and therefor doesnt help at all to grind their teeth down.
Nice fresh hay for that, a bit of fresh fruit, and theyll be fine.
If that piggy food looks as if it got breakfast cereal in, I def. wouldnt feed it to them. Is it properly frosted stuff, like, you can actually see white stuff on it like kellogs frosties or something? weird... what brand is it?
I knew a breeder who never gave his pigs dried food he grew and sprouted his own wheat things, dont ask me what but he kept it while it sprouted and then fed them he also never gave them water until summer because all the water from the sprouting wheat was enough and I have to admit his pigs black selfs and golden red eye selfs were stunning, so dried food is'nt necessary but i'd feel i was starving my babes if i did'nt give them it,