I think she is being wise.
When an artist performs at the SB, they get a huge initial boost, but thee their eras very rarely have longevity as the hype dies down very quickly.
The SB performance was to promote the tour, and then after the tour she will release the album, meaning she has had many months to re-establish herself and gain a wider stanbase.
This will (hopefully) cause her next era to last a long time. I think that is the idea anyway. Either that or her management is a complete mess.
EDIT: I just re-read that and it doesn't make much sense. Essentially what I'm saying is she is making people wait for her so they'll be here for her when she finally releases something.