Bad record keeping can affect others

So I had yet another in a long stream of FNST's this morning. Baby#3 was being persnickity and not wanting to cooperate, which I kept teliing Dr B and Nurse C proved he was just fine. Near the end of my appointment, I reminded Dr B of my "standard" pre-natal next wednesdy, as well as another FNST, when Dr B hits me with the shocking question o the day
"What's your due date again?"
I informed him that the technical due date is April tenth, and he replies "Hunh, that's a ways out yet, in't it?"
"Well, yeah, that's why all the concern and stuff, why?"
"The way Dr A has it written in your records, it looks like the due date is March 30th."
"No. March 30th is wat we were thinking before the ultrasound. All the ultra sounds up till this point have said the exact same thing-April 10."
"Well then, expect your wed. appt. to last a little longer than expected, so we can go over all the information a little better, and weigh all your options then."

Apparently, what happened is this. Instead of useing the lines on my chart provided for writing down estimated due date as factored by last menstrual cycle, and due date as determined by ultrasound(the more effective method), Dr A just kind of randomly jotted all this in the corner, and did it at a crooked diagonal, so it looked like we first thought the kid would be due in April, but it was actually due in March. A week and a half doesn't sound like a long time, but in the land of gestation, it is sometimes critical.
Dr B feels bad, but it isn't his fault, really. By wednseday noonish I will have a much better idea of what is going on, and when to expect the baby.