H!1B visa extension with I-140

[mellowfellow]

I have an H1B visa and an I-140 with a priority date in 2018. I changed my job recently and the new employer is taking time to file my PERM application. My priority date is intact since my I-140 has not been withdrawn and anyways I was with the older company for more than six months after my I-140- was approved.

However will I be eligible for further extensions on my H1B if the employer takes more time to file my PERM and my H1B visa extension runs out?

Thank you.