(a) Beginning on the first day of the 2011-2012 school
year and thereafter:
  (1) Except as provided in paragraph (3) of this subsection,
a member must work in a TRS eligible position and be paid or receive
paid leave from a TRS eligible position at least 90 days during the
school year to receive a year of service credit.
  (2) A substitute as defined in §25.4 of this title
(relating to Substitutes) will be qualified for membership and granted
a full year of service credit by working 90 or more days as a substitute
in a school year, receiving pay for that work, and verifying the work
as provided in §25.121 of this title (relating to Employer Verification)
and paying deposits and fees for the work as provided in §25.43
of this title (relating to Fee on Deposits for Unreported Service
or Compensation).
  (3) In the last school year of service before retirement,
a member serving in an eligible position who worked and was paid for
that work or received paid leave for less than 90 days in the school
year but worked and was paid for that work or received paid leave
for a full fall semester in accordance with the employer's calendar
will receive a year of service credit. If the employer's calendar
does not provide for semesters, a member must work and be paid for
work in an eligible position or receive paid leave from an eligible
position for at least 90 days in order to receive a year of service
credit for the school year before retirement.
  (4) Days that the employer is scheduled to be closed
for business are not included in the 90 days of work required to receive
a year of service credit unless the day(s) are paid holidays by the
employer or the employee was charged with paid leave during the closing.
Holidays that are not included in the required number of work days
for an employee are not counted as paid holidays or days of paid leave.