This would work for Easter Sundays

=YEAR(B2)-YEAR(A2)+(A2<=FLOOR(DATE(YEAR(A2),5,DAY(MINUTE(YEAR(A2)/38)/2+56)),7)-34)-(B2<FLOOR(DATE(YEAR(B2),5,DAY(MINUTE(YEAR(B2)/38)/2+56)),7)-34)

For Easter Mondays change the 34s to 33s and for Good Fridays that would be 36