Shift mode control system

A shift mode control system comprising:

• a control apparatus configured to control a shift mode of a vehicle;
• a first operation device configured to receive a first switching operation to switch the shift mode from an automatic shift mode in which shifting of the vehicle is automatically controlled to a manual shift mode in which the shifting of the vehicle is controlled in accordance with an operation performed by a driver who drives the vehicle;
• and
• a second operation device configured to receive a second switching operation to switch the shift mode from the manual shift mode to the automatic shift mode, wherein
• the control apparatus comprises a processor and a memory coupled to the processor, and
• the processor is configured to
• calculate a speed ratio change amount which is a difference between a first speed ratio set when the shift mode is switched from the automatic shift mode to the manual shift mode in accordance with the first switching operation performed on the first operation device and a second speed ratio set when the shift mode is switched from the manual shift mode to the automatic shift mode in accordance with the second switching operation performed on the second operation device, and
• update the speed ratio change amount set as a switching condition for automatically switching the shift mode from the manual shift mode to the automatic shift mode to the speed ratio change amount calculated by the processor.