Changing employer 6months after I-140 approval

[pradhan06]

Hello,

I understand that if I-140 is approved for more than 6months (180 days) with employer A, you can change to employer B and still keep the priority date and apply for unlimited H1B extensions with the new employer B.

I have a question on this 6months(180 days), does this need to be 180 working days on the calendar?

Or I can change to a new employer keeping my priority date as my I-140 has been approved for more than 6months (it was approved on January 2nd 2019

Thanks for your attention!