What are the tax implications of having a PO Box address on my Business in Pennsylvania?

We are currently residents of Pennsylvania, but are selling our house and moving out of state. We'll be glad to get out of paying the high state income taxes there. However, my e-business (an LLC) has a PO box in Pennsylvania (and for reasons that are too complicated to go into) I need to keep that PO Box for the business. Does this mean Pennsylvania will still expect income tax on that business?