Array formula counting empty cells as zero

Hi. I have this array formula

=MAX(FREQUENCY(IF(ALL!$I$2:$I$5375="League",IF(ALL!$E$2:$E$5375="H",IF(ALL!$L$2:$L$5375=0,ROW(ALL!$L$2:$L$5375)))),IF(ALL!$I$2:$I$5375="League",IF(ALL!$E$2:$E$5375="H",IF(ALL!$L$2:$L$5375>0,ROW(ALL!$L$2:$L$5375))))))

which works fine up to a point. It's looking for the longest sequence of zero's. However the formula is counting blank cells as zero's so as there is more data to be added each week and there are more rows left to be filled then the formula is counting these empty cells as zero's which is some cases produces a false result. To stop this happening I have to limit the range of the formula to the last row where data has been entered. Is there a way round this or does it mean every week I have to update the array formula? Many thanks.