Question for you knowledgable Chevy truck guys

So last year I bought a 2007 Chevy truck with a 5.3L engine with around 20,000 miles on it. It was due for an oil change shortly after I brought it home so I took it to a local dealer. A couple of weeks after the oil change I checked the level and found it to be about an inch above the full mark. I drained about 3/4 of a quart to get it down to the proper mark on the dipstick. I just chalked it up to a mistake by someone and decided I better check next time. Well yesterday the same thing happened when I had the oil changed. I got the attention of the service manager and he confirmed that the oil level was indeed too full and we drained some oil out so the proper level was reached on the dipstick. Here are my thoughts on the possibilities. Maybe the dipstick was exchanged with an improper one before I bought the truck or the dipstick was manufactured improperly. I will have to check the for the proper part # for the truck. I was also wondering if there could have been a change in production specs for the oil capacity sometime during manufacture. Oh, I almost forgot, the technician that performed the oil change said they had also seen that situation on a truck the previous week. Anyone have a thought as to what is going on here?