Classic Leveling without Chromie time (post squish)

As in the title, this question is for after the squish occurs. If I pick a racial starting zone, what happens when I get to 10th level? Does Chromie appear and offer choices for which xpac to level in? Can I ignore her and just keep playing? (Old world, I suppose, since that's where most starting zones are).If so, does everything scale to my level? Can I play it 'in order' ( old world, Burning Crusade, etc) with that same character?Say I haven't purchased SL. When I get to 50 will I just be able to keep progressing through the expansions, hopefully with everything scaled to 50? via /r/wow https://ift.tt/33hyd6f