In preparation for the expansion, we've updated the previous Level 41 level-up bundle to a LEVEL 46 level-up bundle! Just like its predecessor, the Level 46 bundle comes with an instant level-up to 46 (if you aren't already), an exclusive new pet, and a full set of Epic gear for your character.

BUT, for this week only, the Level 46 bundle comes with some extra goodies! Check out tomorrow's announcement for more information on how you can start the expansion with a little head start.
Since you've already taken that path and it obviously works for you, why don't you just make it so that you can buy a "level-up bundle" to any level up to the previous cap? Want to make a lvl 23 twink? Sure, get our lvl 23 bundle with a lot of goodies.

Or even better - make is something like 5 plat per level and allow people to level up from any level to any level. Want to level from 23 to 46? 115 plat.

You can add other stuff too. Delevel option? Pet auto level? I mean, why not?