You can do a max duty day but only a few hours flying, more time can be logged in the BRU crew room than flying. quite a lot of standby, airport, hotel, and home. When you start a series of duties the first day is often a rest day and you start late at night or early in the morning, and if you finish early the morning then the rest of the day is considered rest so it doesnt count as a day off. The up shot of it is short sectors, hub and spoke operation, and time in the hubs while they sort out the freight means it is hard to fly more than 3-400 hrs a year.