Generally yes. They do it on a "lazy" basis, so it'd probably happen within a few months of you hitting the $50k mark. If you want to do it sooner, you can just log into your account and press the "convert now" button. Very easy and seamless.
Generally speaking the upgrade is also not a taxable event.
"At times the world can seem an unfriendly and sinister place, but believe us when we say there is much more good in it than bad. All you have to do is look hard enough, and what might seem to be a series of unfortunate events, may in fact be the first steps of a journey." Violet Baudelaire.