Official comment
@kevin > If you sort a playlist and want it to be in that order (numerically) when you load it on a CDJ-350 which does NOT have the ability to sort, you need to re-number it within rekordbox.
First, sort it the way you want (eg. by BPM ascending).
Next, right-click on any column header and click Renumber Track Order.
Finally, export the playlist and it will now remain in that order when loaded on the CDJ.