Transpose column against repeated cells

3 Formulae.

A2, copied across and dnown:
=IFERROR(INDEX(Main!$A:$I,AGGREGATE(15,6,ROW(Main!$A$2:$A$15)/(Main!$A$2:$A$15<>""),1+INT((ROWS(A$2:A2)-1)/7)),MATCH(A$1,Main!$A$1:$I$1,0)),"")

J2, copied down:
=IF($A2="","",INDEX(Main!$L$1:$R$1,,1+MOD((ROWS(J$2:J2)-1),7)))

K2, copied down:
=IF($A2="","",INDEX(Main!$L$2:$R$15,1+INT((ROWS(K$2:K2)-1)/7),1+MOD((ROWS(K$2:K2)-1),7)))

adjust the bits in red to give yourself some spare capacity... saved as an xlsx. Why are you still using the obsolete .xls format???