Image forming system

An image forming system comprising:

• an image forming portion configured to form an image on a sheet;
• a first feeding portion configured to feed a recording sheet on which an image is to be formed toward the image forming portion;
• a conveyance path configured to convey a recording sheet on which an image has been formed by the image forming portion;
• a second feeding portion comprising a plurality of supporting portions and configured to feed an inserting sheet from one of the plurality of supporting portions, the plurality of supporting portions each configured to support an inserting sheet;
• a detection portion configured to detect information about a remaining amount of inserting sheets supported on each of the plurality of supporting portions;
• and
• a controller configured to execute a job comprising a feeding process of causing the first feeding portion to feed a recording sheet to the image forming portion to form an image thereon and an insertion process of causing the second feeding portion to feed an inserting sheet to be inserted between a plurality of recording sheets,
• wherein the controller is configured to execute a determination process of determining, while the job is executed and on a basis of a detection result of the detection portion, whether or not there is a supporting portion usable as a new feeding source other than a supporting portion serving as a current feeding source of an inserting sheet among the plurality of supporting portions,
• wherein the controller is capable of switching between first control and second control, the first control being control in which the feeding process of a recording sheet is executed in a first mode in a case where it has been determined in the determination process that there is no supporting portion usable as the new feeding source, the second control being control in which the feeding process of a recording sheet is executed in a second mode in a case where it has been determined in the determination process that there is no supporting portion usable as the new feeding source,
• wherein the first mode is a mode in which the feeding process of a current recording sheet is started before the detection portion detects whether or not a last preceding inserting sheet is present on the supporting portion serving as the current feeding source, the current recording sheet being a recording sheet to be fed this time, the last preceding inserting sheet being an inserting sheet preceding the current recording sheet in an order of passing through the conveyance path, and
• wherein the second mode is a mode in which the feeding process of the current recording sheet is started after the detection portion detects that the last preceding inserting sheet is present on the supporting portion serving as the current feeding source.