Merging Time Cards



Can anyone suggest a way to create a 'Change Rule' to merge two time cards (Eg. a Holiday Pay Type and an everyday Pay Type, such as Pay Type 1) into a single time card with a single Pay Type?

So, if an employee entered time (Pay Type 1 - what they would use every day) on a Holiday (which would already have a time card with a Holiday Pay Type), then the system could merge the two time cards together into a single Pay Type that could pay the employee however the new Pay Type is set up - 1.5 Overtime, double time and so forth.

I'm just not sure of how to code a 'Change Rule' that could read two time card (F06116) records and merge into a single time card. Does anyone have, or have you seen, a similar type 'Change Rule' that could do something like this?