Can anybody help me to 计算 out of status 天数

Sorry to post this again.

My I-20 expired because of a typo in expiration date. When I found it, I was already out of status for quite a long time. Then I did reinstatement to complete my study.

My question is:

Do I have a 60 days grace period after I-20 expired? With the grace period, it is less than 180 days, without the grace period, it is more than 180 days. So, it is very important for me whethere there is a 60 days.

Thank you!!!!