reuse labor

[immehelp_100]

i have heard that labor certification can no longer be reused by a company for employee B if the employee A for whom the labor was approved leaves the company.
a) Is this true?
b) If employee A rejoins the company after 2 years can the employer reuse the old labor approval ?

[txh1b]

a. Yes
b. No. It expires in 6 months.