Oil change interval

I need some advice regarding my oil change intervals. With my old car I used to do it twice a year when I got my summer or winter tires changed, usually around 7-8k kms just based on my driving. It seems like this would fit with what the Micra manual recommends as well, except that I bought the car in mid January. Dealer called me today to remind me I am due for my first oil change because of 6 months (only at 5k km right now, and 2500 of that was in the last month). To get this time frame more in line with my tire change season, do you think I could delay it 1 month for the next 3 changes, or should I do it 1 month early for the next 3 changes (not including this one as it's at 6 months already).

I will probably never do it myself, and go to a local shop usually or the dealer depending on cost. I am only going to the dealer that sold me my car right now because they owe me a free oil change :P There is a closer dealer that I would try after this change.