"Check now" for software update is lying to me

I have two streaming stick 4K's.

One is on software 15.0.

The other is on 14.6.4 - but when I go into settings and check for an update, it says I'm up to date.

Is this known behavior?

Also the device with 15.0 has a problem with the Apple TV tile disappearing even though the app is installed, so Roku engineering may want to look into this!