diff --git a/web/src/components/overlay/ExportDialog.tsx b/web/src/components/overlay/ExportDialog.tsx
index c7ac3f83b..a9d597f83 100644
--- a/web/src/components/overlay/ExportDialog.tsx
+++ b/web/src/components/overlay/ExportDialog.tsx
@@ -308,19 +308,18 @@ function CustomTimeSelector({
 
   const timezoneOffset = useMemo(
     () =>
-      /*
-       config?.ui.timezone
-        ? getUTCOffset(new Date(), config.ui.timezone)
-        : undefined
-      */
-      getUTCOffset(new Date(), "Australia/Darwin"),
-    [],
+      config?.ui.timezone
+        ? Math.round(getUTCOffset(new Date(), config.ui.timezone))
+        : undefined,
+    [config?.ui.timezone],
   );
   const localTimeOffset = useMemo(
     () =>
-      getUTCOffset(
-        new Date(),
-        Intl.DateTimeFormat().resolvedOptions().timeZone,
+      Math.round(
+        getUTCOffset(
+          new Date(),
+          Intl.DateTimeFormat().resolvedOptions().timeZone,
+        ),
       ),
     [],
   );
@@ -398,7 +397,7 @@ function CustomTimeSelector({
         </PopoverTrigger>
         <PopoverContent className="flex flex-col items-center">
           <TimezoneAwareCalendar
-            timezone={"Australia/Darwin"}
+            timezone={config?.ui.timezone}
             selectedDay={new Date(startTime * 1000)}
             onSelect={(day) => {
               if (!day) {
@@ -460,7 +459,7 @@ function CustomTimeSelector({
         </PopoverTrigger>
         <PopoverContent className="flex flex-col items-center">
           <TimezoneAwareCalendar
-            timezone={"Australia/Darwin"}
+            timezone={config?.ui.timezone}
             selectedDay={new Date(endTime * 1000)}
             onSelect={(day) => {
               if (!day) {
diff --git a/web/src/components/overlay/ReviewActivityCalendar.tsx b/web/src/components/overlay/ReviewActivityCalendar.tsx
index 1d888705f..7ddc528e4 100644
--- a/web/src/components/overlay/ReviewActivityCalendar.tsx
+++ b/web/src/components/overlay/ReviewActivityCalendar.tsx
@@ -89,7 +89,8 @@ export function TimezoneAwareCalendar({
   onSelect,
 }: TimezoneAwareCalendarProps) {
   const timezoneOffset = useMemo(
-    () => (timezone ? getUTCOffset(new Date(), timezone) : undefined),
+    () =>
+      timezone ? Math.round(getUTCOffset(new Date(), timezone)) : undefined,
     [timezone],
   );
   const disabledDates = useMemo(() => {
@@ -102,7 +103,6 @@ export function TimezoneAwareCalendar({
         0,
         0,
       );
-      tomorrow.setHours(25);
     } else {
       tomorrow.setHours(tomorrow.getHours() + 24, -1, 0, 0);
     }
@@ -127,7 +127,7 @@ export function TimezoneAwareCalendar({
       date.getUTCSeconds(),
     );
     const todayUtc = new Date(utc);
-    todayUtc.setHours(25, todayUtc.getMinutes() + timezoneOffset, 0, 0);
+    todayUtc.setMinutes(todayUtc.getMinutes() + timezoneOffset, 0, 0);
     return todayUtc;
   }, [timezoneOffset]);