Can I get a BA and tonsillectomy in the same week?

Yes both could be done within a week but I do not believe that you will feel great if you do.  Either do both under one anesthesia or give yourself more time in between.  Good luck.

You need to talk to the two surgeons involved. The main issue will be the swelling and pain of the tonsillectomy.  You will likely need about two weeks between procedures and it would not really matter which one you do first.  Good luck!

Although it is nice to combine procedures and minimize downtime, I would keep your current operative schedule the way  it is. You will be well healed from the tonsillectomy by august and will avoid possible problems caused by combining these operations. In elective cosmetic surgery we like to minimize risk. There is a theoretical concern that bacteria can enter the bloodstream during the tonsillectomy and contaminate the breast implant leading to infection or capsular contracture. Although inconvenient I would recommend two separate procedures 4-6 weeks apart. Good luck.