§ 578. Non-liability for penalty and interest. 1. Conditions. The
provisions of this section shall apply to employers who failed to
discharge obligations under this title because of the bona fide belief
that all or some of their employees are covered under the unemployment
insurance laws of other states or of the United States, provided they
paid pursuant to such laws the contributions required thereunder on all
wages of all such employees.

2. Extent. Failure to pay contributions under this title with respect
to such employees shall not render any such employer liable for interest
provided such contributions are paid within ninety days following the
date on which a determination or decision establishing the employer's
liability therefor has become final. If such contributions are not paid
within ninety days following such date, interest shall be assessed only
from such date to the date of payment.