I'm trying to make sense of how you write the dates over there in the UK. I can tell the 28 is the day. Just can't figure out which is the month and which is the year.
Here in the U.S., we do it like this: Month/Day/Year.
Anyways, I do understand your question. It's never likely to be on or around the same date year after year. Nor would it be a home game the following season. It all depends on how the NFL prepares the schedule. Not saying that it may not happen again. It's very possible it could happen that way.
Plus it also depends on the schedule of the facility. Sometimes the owners of the facility may rent the facility out for special events such as concerts. Therefore the NFL would have to schedule the games around these dates.
Looking at Jacksonville's schedule, I'm guessing you saw a game on August 9,2008. If I'm right, then you saw what they consider to be a Pre-Season game. This was their first game of the Pre-Season. Comparing schedules from last Pre-Season to this Pre-Season; their first game wasn't until August 17,2009, and wasn't played in Jacksonville. So you were right, it was an away game this year. Yet in comparing the schedules from 2006 and 2007, Jacksonville's first Pre-Season games were both away. So I hope I answered your question, and didn't confuse you too much.
Cochise gave good advice by saying go to NFL.Com. This site will help answer other questions you might have.