sof
This method returns the latest time one is allowed eating chametz on Erev Pesach according to the opinion of theGRA. This time is identical to the sofZmanTfilaGRA and is provided as a convenience method for those who are unaware how this zman is calculated. This time is 4 hours into the day based on the opinion of the GRA that the day is calculated from sunrise to sunset. This returns the time 4 * shaahZmanisGra after sea level sunrise.
Return
the Date one is allowed eating chametz on Erev Pesach. If the calculation can't be computed such as in the Arctic Circle where there is at least one day a year where the sun does not rise, and one where it does not set, a null will be returned. See detailed explanation on top of the AstronomicalCalendar documentation.