I-140 approved, H-1B expiring soon; should I apply for adjustment of status?

[passion4science]

My I-140 case was just approved, and my H-1B is expiring on Dec 31, 2016. My employer is filing for the H-1B extension for another year (Jan 1, 2017, to Dec 31, 2017) which may arrive in the next three to four weeks.

Can I apply for adjustment of status (I-485) with the current H-1B documents? Or, should I wait for the approval of H-1B extension?

Please suggest.