Image forming apparatus configured to perform initialization process for first consumable and second consumable attached to main casing in accordance with received instruction

An initialization method of initializing at least one of first lifetime information stored in a first consumable memory included in a first consumable or second lifetime information stored in a second consumable memory included in a second consumable,

• the initialization method comprising:
• a reception step, by an image forming apparatus, of receiving an instruction instructing to initialize at least one of the first lifetime information stored in the first consumable memory of the first consumable attached to a main casing of the image forming apparatus or the second lifetime information stored in the second consumable memory of the second consumable attached to the main casing, the first lifetime information being related to a service life of the first consumable, the second lifetime information being related to a service life of the second consumable;
• and
• an initialization step, by the image forming apparatus, of initializing, in accordance with the received instruction, the at least one of the first lifetime information or the second lifetime information that corresponds to a target of initialization that is designated by the instruction.