What is the maximum number of digits that an ephone PIN can have to allow after-hour exempt calling privileges?

4 digits is not the maximum supported PIN length; it is simply below the 8-digit upper limit that CME enforces for after-hours exempt calling.

6 digits falls short of the actual 8-digit maximum and is not the correct upper bound for the after-hours PIN in Cisco CME.

7 digits is not the documented maximum; the CME after-hours PIN feature supports one additional digit, up to 8.

The after-hours PIN configured under Cisco CME ephone or telephony-service after-hours commands accepts a maximum of 8 digits, which is the platform-defined upper bound. This PIN grants a phone user the ability to place calls outside the normally restricted after-hours dialing policy. Exceeding 8 digits is not accepted by the CME parser for this command.

9 digits exceeds the maximum PIN length supported by the Cisco CME after-hours exempt calling configuration and would be rejected by the platform.