Image formation control method and image forming apparatus

An image formation control method for controlling an image forming apparatus including:

• a roll paper supply device configured to roll out roll paper and cut a rolled-out portion of the roll paper to produce a first sheet of a specific size, and convey the first sheet to a specific conveying path;
• a cut sheet supply device configured to convey a second sheet cut to the specific size in advance and accommodated in an accommodating portion to the specific conveying path;
• a printing device configured to execute a print process of forming an image on the first sheet or the second sheet conveyed through the specific conveying path to a print position;
• and a sensor configured to detect the first sheet at a specific position between a position at which the roll paper is cut in the roll paper supply device and the specific conveying path, the image formation control method comprising:
• when continuous print processing in which the print process is repeated a plurality of times is executed,
• determining, by a control device based on a detection state of the sensor, whether or not the roll paper supply device is in a specific state in which the roll paper supply device has conveyed the first sheet to the specific position, for each of the print processes;
• causing, by the control device, the roll paper supply device to execute a process of conveying the first sheet toward the print position when it is determined that the roll paper supply device is in the specific state, for each of the print processes;
• and
• causing, by the control device, the cut sheet supply device to execute a process of conveying the second sheet toward the print position when it is determined that the roll sheet supply device is not in the specific state, for each of the print processes.