diff --git a/app/(authenticated)/calendar/[eventID]/AddEditSignUpSheetForm.tsx b/app/(authenticated)/calendar/[eventID]/AddEditSignUpSheetForm.tsx
index fb865f08..bb6a4be1 100644
--- a/app/(authenticated)/calendar/[eventID]/AddEditSignUpSheetForm.tsx
+++ b/app/(authenticated)/calendar/[eventID]/AddEditSignUpSheetForm.tsx
@@ -148,6 +148,9 @@ function CrewPositionField(props: { parentName: string }) {
   const selectController = useController({
     name: `${props.parentName}.position_id`,
   });
+  // Track the initial selected ID so that, if it's a custom field (but one that existed
+  // before), we can still display the correct value.
+  const [initialSelectedID] = useState(() => selectController.field.value);
   const customController = useController({
     name: `${props.parentName}.custom_position_name`,
   });
@@ -162,14 +165,20 @@ function CrewPositionField(props: { parentName: string }) {
     return [selectController.field.value.toString(10), false];
   }, [selectController.field.value, customController.field.value]);
 
+  const filteredProcessedVals = useMemo(
+    () =>
+      vals
+        .filter((x) => !x.is_custom || x.position_id === initialSelectedID)
+        .map((v) => ({
+          label: v.name,
+          value: v.position_id.toString(10),
+        })),
+    [vals, initialSelectedID],
+  );
+
   return (
     <SelectWithCustomOption
-      data={[
-        ...vals.map((val) => ({
-          label: val.name,
-          value: val.position_id.toString(10),
-        })),
-      ].filter(Boolean)}
+      data={filteredProcessedVals}
       value={value}
       isCustomValue={isCustom}
       onChange={(newValue, isNew) => {
diff --git a/app/(authenticated)/calendar/[eventID]/page.tsx b/app/(authenticated)/calendar/[eventID]/page.tsx
index eaca27ad..462ae136 100644
--- a/app/(authenticated)/calendar/[eventID]/page.tsx
+++ b/app/(authenticated)/calendar/[eventID]/page.tsx
@@ -12,7 +12,7 @@ import { EventObjectType, getEvent } from "@/features/calendar/events";
 import {
   canManage,
   canManageAnySignupSheet,
-  getAllNonCustomCrewPositions,
+  getAllCrewPositions,
 } from "@/features/calendar";
 import {
   CrewPositionsProvider,
@@ -90,7 +90,7 @@ async function ShowView({
     // TODO(WEB-40): this pre-loads quite a bit of information that we don't actually need until you go to edit a sheet.
     //  Would be better to either load it on-demand dynamically, or move the edit view to a sub-page.
     const [positions, members] = await Promise.all([
-      getAllNonCustomCrewPositions(),
+      getAllCrewPositions(),
       getAllUsers(),
     ]);
     return (
diff --git a/features/calendar/crew_positions.ts b/features/calendar/crew_positions.ts
index aa538123..fc3f3dae 100644
--- a/features/calendar/crew_positions.ts
+++ b/features/calendar/crew_positions.ts
@@ -7,15 +7,13 @@ export interface CrewPositionType {
   admin: boolean;
   brief_description: string;
   full_description: string;
+  is_custom: boolean;
 }
 
-export function getAllNonCustomCrewPositions(): Promise<CrewPositionType[]> {
+export function getAllCrewPositions(): Promise<CrewPositionType[]> {
   return prisma.position.findMany({
     orderBy: {
       position_id: "asc",
     },
-    where: {
-      is_custom: false,
-    },
   });
 }