modern oil is great!!!
modern oil can last pretty long!
i believe the owners manual will state to change it out after a year tho.
in my brothers truck, he doesnt drive much, he hit's 6k every 6 months, and I change it then.
(not very scientific, more anecdotal...but you get the picture!)
I think it will be fine the way you are doing it now.
and also, in Texas...it's already Spring time!! lol
I chose 6k intervals because that's what my 3rd gen TL's maintenance reminder on the dash averages.. sometimes it'll hit 7k intervals and some times it will hit 5k intervals. I chose 6k intervals on all my families cars, to make it easier on myself on remembering mileages. For cars that dont have a "maintenance reminder" , like my bros Truck
your magic number seems to be 5k oil change intervals.