diff --git a/app/javascript/SignupRoundsAdmin/MaximumEventSignupsPreview.tsx b/app/javascript/SignupRoundsAdmin/MaximumEventSignupsPreview.tsx
index baeea0d781..4a195ef2ac 100644
--- a/app/javascript/SignupRoundsAdmin/MaximumEventSignupsPreview.tsx
+++ b/app/javascript/SignupRoundsAdmin/MaximumEventSignupsPreview.tsx
@@ -99,7 +99,7 @@ export default function MaximumEventSignupsPreview({
   );
 
   const maximumEventSignups: EditingScheduledValue<string> = useMemo(() => {
-    const parsedSignupRounds = parseSignupRounds(signupRounds);
+    const parsedSignupRounds = parseSignupRounds(signupRounds, timezoneName);
     return {
       timespans: parsedSignupRounds.map((round) => ({
         start: round.timespan.start?.toISO(),
@@ -107,7 +107,7 @@ export default function MaximumEventSignupsPreview({
         value: round.maximum_event_signups?.toString() ?? 'not_yet',
       })),
     };
-  }, [signupRounds]);
+  }, [signupRounds, timezoneName]);
 
   return (
     <ScheduledValuePreview
diff --git a/app/javascript/UIComponents/ScheduledValuePreview.tsx b/app/javascript/UIComponents/ScheduledValuePreview.tsx
index f6d50944b9..a3304c0fc8 100644
--- a/app/javascript/UIComponents/ScheduledValuePreview.tsx
+++ b/app/javascript/UIComponents/ScheduledValuePreview.tsx
@@ -166,6 +166,11 @@ function ScheduledValuePreviewCalendar<ValueType>({
     return <></>;
   }
 
+  // If there's only a single change point (not a range), don't render a calendar
+  if (earliestChange.toMillis() === latestChange.toMillis()) {
+    return <></>;
+  }
+
   if (latestChange.diff(earliestChange, 'months').months > 6) {
     return <>{t('scheduledValuePreview.tooLong')}</>;
   }
@@ -259,6 +264,7 @@ function ScheduledValuePreview<ValueType>({
   const [arrow, setArrow] = useState<HTMLDivElement | null>(null);
   const dateElementMapRef = useRef(new Map<number, HTMLElement>());
 
+  // eslint-disable-next-line react-hooks/refs
   const focusedDateElement = focusedDate ? (dateElementMapRef.current.get(focusedDate.valueOf()) ?? null) : null;
 
   const { styles, attributes, state } = useLitformPopper(tooltip, focusedDateElement, arrow);