61.160 contains the requirements for an R-ATP certificate, and there is a list of FAA approved institutions that are eligible to graduate applicants to meet the R-ATP requirements.
The increased qualification requirements were enacted in August 2013, and therefore these schools' LOAs are all issued after that date.
If a pilot had graduated from one of these schools' programs prior to the issuance of the LOA, does it still grant them the eligibility for reduced minima? Is the authority retroactive? If so, by how much time?