4.4 When to Use Advanced Code Security Configuration Bits
In the context of embedded applications, it is recommended that the OTP ICSPDIS and SAFLOCK Configuration Bits of the microcontroller be programmed during the final phase of product development. It is strongly advised that these Configuration Bits not be programmed during the development or prototyping stages. Devices that have had the ICSPDIS Configuration bit enabled will permanently have their programming and debugging interface disabled, meaning that it will no longer be possible to reprogram or erase those devices ever again.