[SOLVED]Integrate (Indirect(address))

I have this formula:

=SUMIF('Fcst template'!$A:$A,$A6&"*",OFFSET('Fcst template'!$A$1,0,MATCH(C$4,'Fcst template'!$5:$5,0)-1,65535,1))

Every now and then, I need to delete/replace the worksheet 'Fcst template' with another one with the same name. When I do this, #REF would appear.

So I stumbled across this (Indirect(address)) function and was wondering if its possible to be integrated into my existing formula.

Thanks