How to know if Old H1B is still valid

Hi Members

I came to US on H4 in 2008 and applied for H1B through employer-A and got the approval from 2008 to 2011 but never worked in US and went back to India in 2008.

I came back in US on H4 in 2015 and have been working on H4-EAD with employer-B for last couple of years but due to recent news on H4-EAD, I am thinking of switching back to my old H1B.

Is there a way to find out if that old H1B (2008-2011) is still valid and can be revived? If so, I can try to switch job and file H1B out of status as my current employer dont handle H1Bs. So I wanted to be sure on H1B validity before trying for job change.

Please suggest!

Thanks

PJ