> highway	primary	way	The next most important roads in a country's system. (Often link larger towns.)

https://wiki.openstreetmap.org/wiki/Key:highway

> highway	trunk	way	The most important roads in a country's system that aren't motorways. (Need not necessarily be a divided highway.)


This road is not the most important. A different one might be if it gets built. 
This road is also not internationally ( E ) important

Discuss before you change. 