In the preliminary allocation, the allocation of balancing grades is unsatisfactory because it is based on the participants DOPs. A participant DOP is prepared from the refinery LP model using its share of processing unit capacity. The DOPs are prepared before the start of the reference month. At that time, the exact refinery unit capacity available for sharing between the participants, during the month, is not known. Also, the average balancing-grade product prices prevailing during the month, which are used to drive the LP, are not known. Participants may be using approximate data on processing unit capacity available to them and balancing-grade product prices in their refinery LP model. The result is that the optimization of balancing-grades production is not on the same basis in the two participants LPs.

The final allocation is done after the end of the reference month. At that time, the monthly average unit capacity of each processing unit available to participants is known with certainty. Also, the monthly average balancing grade products published prices are known. Therefore, modeling the refinery unit capacities available to each participant can be accurate. Both models are driven by an average Mean of Platt or other published product price quotes prevailing during the month. Crude run, fixed grade productions, and process stocks drawdown or buildup are entered in the LP models from the preliminary allocation of the participants.

The final product allocation process has two main parts to it: running the allocation LPs, then rerunning the allocation procedure.