What is the ERC (European Research Council)? Find more information here:

-ERC website
-Euresearch: the Swiss guide to European research & innovation

Q: If there are two dates of the PhD award on the PhD certificate, which one is the reference date?

The reference date for the calculation of the beginning of the eligibility period should be the date of the actual award of the degree according to the national rules in the country that the degree was awarded. In the case of applicants having been awarded several PhDs, the reference date is the award date of the first PhD.