I am guessing this is a 5.5 gal batch, 70 % efficiency, with 10 srm Munich malt. So “by the numbers” it could be on the fringe of either a slightly darker version of a 6b Blond Ale, or a lightly hopped version of a 10A American Pail Ale.
Best advice it to find a good BJCP Judge to taste it and let you know the best category to put it in. It is all about how it tastes in competition!
Based on how it tastes, it’s either an APA (10A), an American amber (10B) or a specialty beer (23A).
To decide, taste the beer with the BJCP guidelines in front of you, or have an experienced BJCP judge taste the beer and give you their opinion.
The oddities are the oats and the relatively high level of aroma hops. If the oat character is evident, the malt flavor and color is too dark for an APA and the hops are too prominent for it to be an American Amber, then it’s a specialty beer. In that case, call it “a hoppy oatmeal American amber ale.”