2nd H1b extension application when 1st H1b extension pending

[us97007]

Hi all, 

I need advice in the following situation: 

My 5th year of H1b expired at 1/7/2016, and company applied for 1st one year extension in Oct 2015 under regular processing. This extension is still pending. 

Since my 6th year of H1b will expire at 9/30/2016, my employer intends to file 2nd one year extension under premium processing in April 2016 to extend H1b till 9/30/2017 (based on a pending PERM that is over 1 year old, under BALCA). 

Can you please let me know what's the appropriate course of action here? Specifically I intend to know: 

1) Will 2nd one year extension needs to be filed for a period from 9/30/2016 to 9/30/2017 (Note: 9/30/2016 is the expiration date for which 1st extension was filed, which is still pending)? 

2) Can we have processing of 2 one year extensions for H1b at the same time? Is it possible? 

Please let me know if I didn't clarify my situation enough, and I great appreciate your help in this!!!