Supersession & cutover
How a released Revision or Replacement Part phases over, the cutover fields you tune per item, and how MRP and Get Method honor supersession downstream.
For a Revision or Replacement Part affected item, release auto-writes a from the old item to the new one. You don't create it by hand — you only tune how the phase-over behaves, per affected item, through the cutover fields.
A Version supersedes nothing, because it edits the same item. A New Part supersedes nothing either, because it's net-new — there's no predecessor to phase out. Only the two change types that derive a new item from an existing one write a supersession.
Only Revision and Replacement Part supersede.
The rule is the predecessor: a Revision phases the old revision over to the new one, and a Replacement Part phases the affected part over to the new number. Version and New Part have no old item to redirect, so release skips supersession for them entirely.
Cutover fields
Set these on a Revision or Replacement Part affected item before you release.
Supersession modes
The controls what downstream planning does with the old item:
| Mode | Behavior |
|---|---|
| Consume First | Exhaust on-hand of the old item, then redirect new demand to the successor. |
| Prefer New | Redirect new demand to the successor immediately. |
| Stock Only | Keep only a minimum service reserve of the old item; no production use. |
| No Stock | Drop the old item from planning entirely. |
Only Consume First and Prefer New redirect demand.
Those two modes tell planning to route the old item's demand — times its conversion factor — to the successor. Stock Only and No Stock govern the old item's own stocking rather than redirecting to a successor.
How downstream honors it
Once a supersession is effective (on or after its successor-effectivity date), two systems act on it:
- MRP redirects planned demand for the old item to the successor, applying the conversion factor and collapsing multi-hop chains (if A was superseded by B and B by C, demand routes straight to C).
- Get Method substitutes the successor onto Buy and Pull bill-of-materials lines when a new job is created, recording the source item so the substitution is traceable.
Release never touches work already in flight.
Existing stock stays on the old item, and jobs already created keep the exact materials and method version they were built against. Open documents follow the same rule: a purchase order, sales order, or quote line that names the old item keeps it; nothing warns or rewrites it at release. Supersession only steers forward planning — a job created after the successor's effectivity date picks up the new item; one created before it does not shift. That's what makes releasing safe on a busy floor.