1. A computer-implemented method for balancing resource loads, comprising: receiving a work request; determining for each of a plurality of service locations a probability of servicing said work request within a target time, wherein said determined probability includes determining a relative probability for each service location included in the plurality of service locations by calculating a number of opportunities to service said work request within said target time by each service location included in the plurality of service locations, wherein said number of opportunities is calculated as a function of a weighted advance time (WAT), where WAT is a weighted advance time for a work request assigned to said service location; selecting at least a first service location having at least one of a greatest determined probability of servicing said work request within said target time and a sufficient determined probability of servicing said work request within said target time; and assigning said work request to said selected service location.