Early reports on the local newspaper Gazette website said he was shooting at cars in a parking lot before going into PP. Then the strange tale of taking things inside PP and then taking them back outside and placing them there on the presser.
So, no credible report to indicate this wasn’t anything other than a planned attack on PP.
As you point out, this is a very strange situation. If he hated PP why did he shoot cops but didn’t hunt out employees and patients of PP. It almost seems as though he took over PP, planted bombs but decided not to kill anyone face to face or to detonate his bombs. Yet he still shot at and fought the the police?? Odd.