I had the aircraft today , and I got it wrong. They operate L/H pack on ground and the R/H pack got a trip off without even being on. In flight all systems work properly. I even had this scenario with both packs "off", I got a double pack trip off. The APU is running at the time. The only way I could reset packs was to pull ovht cb behind F/O's seat and operate pack for a few seconds. Weird snag if you ask me.