Originally posted by stooper:
E.g. for 1 bus, the actual running time is 8h00 exactly (excluing SWING ONLY), the payhour is also exactly 8h00.
Another bus, actual running time: 8h04, payhour: 8h06
Another bus, actual running time: 9h02, payhour: 9h33
a 3rd bus, actual running time: 9h48 (typo), payhour: 10h42
an E shift bus, actual running time: 11h29, payhour: 13h14
I have finally figured out how it's calculated!

Thanks to an article in the Today newspaper a few days ago. The magical numbers are 8 and 1.5!

Ok! Based on the above examples.
For 26E, the actual overtime is 3h29 (11h29 - 8h) Multiply this by 1.5 and it's rounded off to 5h14. Add this back to the basic time, and you get 13h14!
For 17S, the actual overtime is 1h48 (9h48 - 8h). Multiply by 1.5 and you get 2h42. Add this back to 8h and you get 10h42!