AC 140 portability 问题

concurrently file 140&485 at the same day,now it has been 190 day. if I140 isapproved ,it is safe to change job or not?
for AC-21 portability,some people tell me that 485 pending for 180 day start from the day when I140 approve,not start from the day filed 485. is it true?
they tell me that before concurrently filing, I485 is submit after I140 approved.then is the 180 day starts counting.after concurrent filing,they follow the same rule, 180days starts counting after 140 approved.