FII debt limit replacement period: five business days for substitution; unutilised limits withdrawn and reallocated promptly. A replacement period of up to five business days is permitted for FIIs to substitute disposed or matured debt instruments; custodians must monitor and report unutilised limits upon expiry of that period. Any unutilised limit after five business days will be withdrawn and reallocated to the next waitlisted entity. Switches by sell off and replacement between government securities and corporate debt are not permitted due to separate individual limits.