When should you change the automatic transmission fluid in my 2008 Honda Accord

Best round figure I've seen for long lasting &trouble-free Honda transmissions is about every 30K miles in normal driving conditions. IF most of what you do is say, 80% highway , then I'd stretch it to 50K. I would also strongly recommend (no matter who or where it's changed) , that you ONLY use genuine HONDA fluid. MY opinion. Doesn't matter what brand vehicle , Trans fluid is one thing I always recommend to use FACTORY fluid!..LAST--DO NOT FLUSH!!!!!!!!!!!!!!!!! ONLY drain & fill! (A little under 4 quarts).