Time calculation rule for override rate

Hi All,

We have a requirement where if an employee works for a particular task (custom attribute) meaning if employee enters time against that value on the timecard, then automatically a specific rate should be override and calculate the amount instead of with standard hourly rate.

If employee hourly rate is $15 per hour and entered the regular 8 hours against a "special task A" then employee hours should be multiplied by $20 instead of $15 (standard employee hourly rate).

Here is the calculation: Assume employee hourly rate is $15 and override rate is $20.

1. Employee enters regular 8 hours without task selected. Now amount per day is 8*$15 = $120