Postponement of primary day.

(b) If a primary is held on a day prescribed by subdivision (1) of subsection (a) of this section, the day of the primary shall be considered to be the day on which such primary would have been held except for subdivision (1) of said subsection, for all other purposes including the calculation of any period of time having reference to such primary, except that the calculation of any deadline relating to a person becoming eligible to vote in such primary shall be made from the day on which the primary is actually held.