Robot-card relay
A
1207
B
286
Id
C20
Job
remove
Reason
Order and units are stated, not guessed.
Complete source
A fictional robot card tray starts 1207, uses 286, then receives 149.
Status
Original fictional ordinary practice; teach source/help before any own application.
Title
Robot-card relay
After own work: adult practice possibility
921 after use; 1070 after arrival; 1070−149=921.