this way of expressing time isn't used very often. i think it's military-style. the military style start the clock at 00:00 (12:00am), and goes up to 23:59 (11:59pm). so 1am would equal 01:00, and spoken "oh one hundred hours". it's a little weird.
so, to answer your question, "1956 hrs" means "seven fifty-six pm"