Lol the little hooligan
Well if you were to calculate at the lower end of the scale how much food they're supposed to have for their age and bodyweight (weigh it the first time, after that you can guestimate) and divide by three, and feed before work, after work and then at say 7-8pm (assuming you're doing a 9-5) they'd be fine. They probably sleep for 90% of the time you're at work anyway!
I know cats are supposed to be "obligate carnivores who seldom overeat" but mine eat anything they can get their norty paws on (I can't have a fruit bowl out with anything besides apples and oranges in it, nothing is safe, not vegetables - they were even trying to nick my vodka and diet coke last night?! ) also they always finish their bowl and I'm sure would eat twice the amount if they could - plus I can't leave their food out as the dog sits there looking over them until they finish then "washes up". I don't stick to a particulartly strict routine - they have to wait an extra couple of hours for breakfast on the weekend and as my daughter's their mum they don't usually eat during "school hours" and sometimes have to wait for their third meal (half a tin of morrisons mycat gourmet each at the mo, only 40p for 185g and it's pretty good stuff with 55% fish) as late as 8.30 or 9. And they seem quite happy little monsiteurs