I have premium account. I downloaded playlist and play them on the road, to avoid eating up too much of my data plan.
This morning I got a reminder from my carrier that not much of the monthly data quota is left. So I checked the reason.
Turns out the green downward arrows attached to many downloaded songs have been greyed out. There is no message or alert from Spotify telling me this song is no longer downloaded, Spotify just smartly stream it again.
Is this a bug or feature?