b11=IFERROR(INDEX(Sheet1!$C:$C,SMALL(INDEX((Sheet1!D$6:D$50<>LOOKUP(2,1/((A$11:A11<>"")*(RIGHT(A$11:A11,4)<>"Seat")),A$11:A11))*10^10+ROW(Sheet1!D$6:D$50),0),ROW(B11)-MATCH(LOOKUP(2,1/((A$11:A11<>"")*(RIGHT(A$11:A11,4)<>"Seat")),A$11:A11),$A:$A,0)+1)),"") 
=IFERROR(INDEX(Sheet1!$C:$C,SMALL(INDEX((Sheet1!D$6:D$50<>LOOKUP(2,1/((A$11:A11<>"")*(RIGHT(A$11:A11,4)<>"Seat")),A$11:A11))*10^10+ROW(Sheet1!D$6:D$50),0),ROW(B11)-MATCH(LOOKUP(2,1/((A$11:A11<>"")*(RIGHT(A$11:A11,4)<>"Seat")),A$11:A11),$A:$A,0)+1)),"")
Try this and copy across