Standing orders already tend to get too long and bulky. Adding another 5-7 lines to them would just be another annoyance. As De-Legro says, that would also be a chore that the Marshal would have to do, and it would never get done. Because really, what's the point? Are they the latest ones? Or are they outdated because the marshal hasn't logged on, and you'll have to go looking for the new ones anyway, so hey'll just be an annoyance.