A late lingering Tree Sparrow visitor!

This time of year especially I am more alert to noticing the difference in birds as I watch and wait for sight of returning migrants. But when I saw this sparrow this morning, something didn't seem right to my mind about this Chipping Sparrow? No, of course not, Chipping Sparrows don't have a central breast spot like this bird did! A Tree Sparrow?! But they are all gone now, aren't they?! But maybe not? Does it have a bi-coloured bill? I changed lenses and strived for a closeup that would show the bill. Yes! It was bicoloured! Wow! A Tree Sparrow indeed! Quite a sighting!, But then we did have snow yesterday! But no on ground accumulation resulted. Maybe this little fellow is starting to feel right at home here, even this late in the season. Go away little bird, Go north where you should be at this time of year. I mean further north! We are finished with winter here!!