Transmission shifting on any modern vehicle is controlled by the computer. There is a multitude of things that can cause late, erratic and hard shift, outside the transmission. The problem could be a transmission issue, but just as likely may not.
Pull the transmission dipstick, smell and look at the fluid. Certainly not definitive, but black or burned smelling fluid indicates high likely hood of transmission problems.
Best is to find a local mechanic, known for honesty and diagnostic skills. Drive with them and point out the problem, if it will occur.
The type of person you are looking for will talk about scanning the PCM and doing a pressure test. Avoid anyone that talks about removing or disassembling the transmission, without diagnosing the problem.