I am in the exact situation as you except that my EAD already expired and I left the job 2 weeks ago. But the employer said they will hire me back if I get EAD soon, within reasonable time. Yes, my TPS is approved, only EAD is being delayed because I applied later around April. Its pending in Nebraska. I will try calling them again to expedite. Also, I heard asking local Congressman's office to expedite the case may be helpful. Fingers crossed. Good luck to you as well. Keep us updated.