diff --git a/admin-wcc-app/components/EditMentor/EditMentorForm.tsx b/admin-wcc-app/components/EditMentor/EditMentorForm.tsx
index cf2845f5..0bfda8b9 100644
--- a/admin-wcc-app/components/EditMentor/EditMentorForm.tsx
+++ b/admin-wcc-app/components/EditMentor/EditMentorForm.tsx
@@ -101,6 +101,7 @@ export default function EditMentorForm({ mentorId }: EditMentorFormProps) {
     control,
     handleSubmit,
     reset,
+    setValue,
     formState: { errors },
   } = useForm<EditMentorFormData>({
     resolver: zodResolver(editMentorSchema),
@@ -165,7 +166,7 @@ export default function EditMentorForm({ mentorId }: EditMentorFormProps) {
       longTerm: data.mentorshipType.includes('LONG_TERM') ? { numMentee: 1, hours: 2 } : null,
       adHoc: data.mentorshipType.includes('AD_HOC')
         ? data.monthAvailability
-            .filter((m) => m.enabled)
+            .filter((m) => m.enabled && m.hours > 0)
             .map((m) => ({ month: m.month, hours: m.hours }))
         : [],
     },
@@ -321,7 +322,7 @@ export default function EditMentorForm({ mentorId }: EditMentorFormProps) {
         <PersonalInfoSection control={control} errors={errors} />
         <BioSection control={control} errors={errors} />
         <SkillsSection control={control} errors={errors} />
-        <MentorshipAvailabilitySection control={control} errors={errors} />
+        <MentorshipAvailabilitySection control={control} errors={errors} setValue={setValue} />
         <ResourcesSection control={control} />
       </Stack>
 
diff --git a/admin-wcc-app/components/EditMentor/MentorshipAvailabilitySection.tsx b/admin-wcc-app/components/EditMentor/MentorshipAvailabilitySection.tsx
index 6ec1def6..c8718080 100644
--- a/admin-wcc-app/components/EditMentor/MentorshipAvailabilitySection.tsx
+++ b/admin-wcc-app/components/EditMentor/MentorshipAvailabilitySection.tsx
@@ -30,7 +30,11 @@ const MONTHS = [
 
 const monthLabel = (month: string) => month.charAt(0) + month.slice(1).toLowerCase();
 
-export default function MentorshipAvailabilitySection({ control, errors }: FormSectionProps) {
+export default function MentorshipAvailabilitySection({
+  control,
+  errors,
+  setValue,
+}: FormSectionProps) {
   const mentorshipType = useWatch({
     control,
     name: 'mentorshipType',
@@ -143,7 +147,12 @@ export default function MentorshipAvailabilitySection({ control, errors }: FormS
                           control={
                             <Checkbox
                               checked={field.value}
-                              onChange={(e) => field.onChange(e.target.checked)}
+                              onChange={(e) => {
+                                field.onChange(e.target.checked);
+                                if (!e.target.checked) {
+                                  setValue?.(`monthAvailability.${index}.hours`, 0);
+                                }
+                              }}
                               size="small"
                             />
                           }
@@ -159,9 +168,11 @@ export default function MentorshipAvailabilitySection({ control, errors }: FormS
                         <TextField
                           {...field}
                           value={value}
-                          onChange={(e) =>
-                            onChange(e.target.value === '' ? 0 : Number(e.target.value))
-                          }
+                          onChange={(e) => {
+                            const nextHours = e.target.value === '' ? 0 : Number(e.target.value);
+                            onChange(nextHours);
+                            setValue?.(`monthAvailability.${index}.enabled`, nextHours > 0);
+                          }}
                           type="number"
                           size="small"
                           label="hours"
diff --git a/admin-wcc-app/components/EditMentor/types.ts b/admin-wcc-app/components/EditMentor/types.ts
index 133e843c..b2b59ce8 100644
--- a/admin-wcc-app/components/EditMentor/types.ts
+++ b/admin-wcc-app/components/EditMentor/types.ts
@@ -1,4 +1,4 @@
-import { Control, FieldErrors } from 'react-hook-form';
+import { Control, FieldErrors, UseFormSetValue } from 'react-hook-form';
 import { EditMentorFormData } from './schema';
 
 export type { EditMentorFormData } from './schema';
@@ -6,4 +6,5 @@ export type { EditMentorFormData } from './schema';
 export interface FormSectionProps {
   control: Control<EditMentorFormData>;
   errors: FieldErrors<EditMentorFormData>;
+  setValue?: UseFormSetValue<EditMentorFormData>;
 }
diff --git a/src/main/java/com/wcc/platform/domain/cms/pages/mentorship/MenteeSection.java b/src/main/java/com/wcc/platform/domain/cms/pages/mentorship/MenteeSection.java
index 02163240..bb345c6e 100644
--- a/src/main/java/com/wcc/platform/domain/cms/pages/mentorship/MenteeSection.java
+++ b/src/main/java/com/wcc/platform/domain/cms/pages/mentorship/MenteeSection.java
@@ -52,11 +52,13 @@ public MenteeSection toDto() {
 
   /**
    * Converts to a DTO scoped to the given mentorship cycle. For AD_HOC cycles the adHoc
-   * availability list is filtered to only the entries whose month matches the cycle month, so that
-   * mentors unavailable in the current cycle month are not surfaced by the AD_HOC type filter.
+   * availability list is filtered to only the entries whose month matches the cycle month and that
+   * declare more than zero hours, so that mentors unavailable in the current cycle month (or with no
+   * real availability, i.e. 0 hours) are not surfaced by the AD_HOC type filter.
    *
    * @param cycle the active mentorship cycle; when null or LONG_TERM the full adHoc list is kept
-   * @return a MenteeSection DTO with adHoc availability filtered to the current cycle month
+   * @return a MenteeSection DTO with adHoc availability filtered to the current cycle month and to
+   *     entries with positive hours
    */
   public MenteeSection toDtoForCycle(final MentorshipCycle cycle) {
     if (cycle == null
@@ -66,7 +68,10 @@ public MenteeSection toDtoForCycle(final MentorshipCycle cycle) {
       return toDto();
     }
     final List<MentorMonthAvailability> filteredAdHoc =
-        adHoc.stream().filter(a -> Objects.equals(a.month(), cycle.month())).toList();
+        adHoc.stream()
+            .filter(a -> Objects.equals(a.month(), cycle.month()))
+            .filter(a -> a.hours() != null && a.hours() > 0)
+            .toList();
     return new MenteeSection(idealMentee, additional, longTerm, filteredAdHoc);
   }
 }