Concerning the new AP system...

This has nothing to do with skill points. 0_0
If you promote late you keep all that you lost. (i.e. if you promote to magician at level 11, you get 10 SP). This has to do with your ability points resetting upon promoting to 1st job, and how any added HP/MP impact your final stats. The SP system remains unchanged from what it used to be before the recent patch.

Are you sure? My friend advanced late and he lost the sp. Check your sp to make sure you have the right amount unless nexon fixed it now.