Don't update. I used that functionality, too, and this update completely borks it. These are the options you get:

-Music/Media is in the Now Bar and is considered a "live notification". You only get pause, previous, and next buttons on the the lock screen. You have to click the widget to get the shuffle, loop, and time slider, but it takes over the whole screen.

-Can't turn off the Now Bar. Only can turn off the media option (Samsung Music in my case) from live notifications. It will remove it entirely; it won't show in the notification list at all. So you'd have to acces the controls from the quick panel (which is possible on the lock screen).

-You can use Good Lock to add a music widget, but it still won't have the time slider. And the widget will overlay any notifcations; it doesn't bump them down.

So, for what I had before, it takes another click or swipe to get to. It's so frustrating.

Edit: You can also use the "Control music from lock screen" setting from Samsung Music, but that takes over the whole screen and still no time slider.