Notwithstanding the provisions of subsection (a) failure to file a claim within the period prescribed in such subsection shall not be a bar to such right unless objection to such failure is made at the first hearing of such claim in which all parties in interest are given reasonable notice and opportunity to be heard.

Notwithstanding the provisions of subsection (a), a claim for compensation for death or disability due to an occupational disease which does not immediately result in such death or disability shall be timely if filed within two years after the employee or claimant becomes aware, or in the exercise of reasonable diligence or by reason of medical advice should have been aware, of the relationship between the employment, the disease, and the death or disability, or within one year of the date of the last payment of compensation, whichever is later.