Not su

You can replace C9 with the following expression:

INDIRECT("C"&MATCH(R[-4]C,R[-11]C[-9]:R[-11]C[-3],0)+3,0)

Of course, your own INDIRECT is somehow producing an A1 reference in a
sheet where other formulas are in R1C1. I hope you are not as confused
using it as I am <g. Good luck!

Does this help?

Kostis Vezerides