Instruction  bid preferences are often used to provide the N-PBS Scheduler with more options for creating a legal block before entering Denial mode.

Instruction bid preferences provide special instructions that tell the N-PBS Scheduler how to manage specific bid preferences, or what to do if it can’t construct a legal block using your initial bid. Instruction bid preferences tell the N-PBS Scheduler what restrictions to remove when processing your bid, in order to complete your block.

Denial mode occurs if the N-PBS Scheduler could not award you a block that reaches the minimum credit window while honoring all of your bid preferences. In Denial mode, the N-PBS Scheduler removes the Set Condition, Avoid Pairings and Prefer Off preferences one at a time attempts to build your block above the minimum credit value using as many of these preferences as possible.

Redo From Line is always used with Forget Line, but Forget Line can be used alone. These instructions usually add pairings back into your pairing pool that the N-PBS Scheduler can consider adding to your block