Why does my transit date keep changing?

i orderd a palm treo from ebay on 2-9-09 it got labeled 2-10-09 it was not on transit until 2-14-09 and every time i keep checking it the date changes like it says in transit 2-17-09 does that mean its still on its way? its first cl mail from planted pda the phone is coming from Tennessee i live in elpaso driving takes 21hours if your going at 55 and on air plane it takes 2 hours can any one tell me why my transit date keeps changing and when i might get my phone?