Meaning of Counterfoil Req: Y in Gcsm notes

[Fatima98]

Hi! We applied for my sisters visit visa in Jan 2021 and still only eligibility is in review. I received her GCSM notes today. And it says this. What does this mean?

ASSESSMENTS:
Eligibility: review required
Security:
Criminality: passed
Info sharing: in progress
Final:
Counterfoil Req: Y