You meant the negative bonus exp? Never was able to get on to use it. The bonus exp causes the massive login and queue spike. Thus netting me less, or no, exp.
You can be happy to know you will get less exp then before because they nerfed the dps of all charm pet classes so your groups will now level slower after you get in. Sheer Genius!
I haven't been able to login to play for the entire duration of this "bonus" because of the 4+hours long queue's.