I have the music to “Smoke Gets in Your Eyes” in G major. 1st 16 measure are in G major. Next 6 measures are in E flat. Then last 10 measures switch back to G major. I all sounds right. How does the E flat part logically fit into the G major scale.
it doesn’t. it’s just a dramatic key change in that particular song/arrangement.
if it was E minor then the relationship would be relative minor.
but in this case it’s key change