diff --git a/src/components/Table/Columns/timezone.tsx b/src/components/Table/Columns/timezone.tsx
index d4a9c4b..affae17 100644
--- a/src/components/Table/Columns/timezone.tsx
+++ b/src/components/Table/Columns/timezone.tsx
@@ -1,69 +1,72 @@
-import { memo, ReactNode, useEffect, useState } from 'react'
+import { memo, ReactNode, useCallback, useEffect, useState } from 'react'
 import { Select, SelectProps } from 'antd'
 
+import { OmitExtends } from '@utils'
+import { findTimezoneId, rawTimezones, TimezoneId } from '@utils/datetime'
 import { SimpleTimezoneDto } from '@api'
 
 import { columnPropsOther, makeColumn } from '.'
 
-export const rawTimezones = {
-    'Калининград': 2,
-    'Москва': 3,
-    'Самара': 4,
-    'Екатеринбург': 5,
-    'Омск': 6,
-    'Красноярск': 7,
-    'Новосибирск': 7,
-    'Иркутск': 8,
-    'Чита': 9,
-    'Владивосток': 10,
-    'Магадан': 11,
-    'Южно-Сахалинск': 11,
-    'Среднеколымск': 11,
-    'Анадырь': 12,
-    'Петропавловск-Камчатский': 12,
-  }
+const makeTimezoneLabel = (id?: string | null, hours?: number) =>
+    `UTC${hours && hours > 0 ? '+':''}${hours ? ('0' + hours).slice(-2) : '~??'} :: ${id ?? 'Неизвестно'}`
 
 export const timezoneOptions = Object
     .entries(rawTimezones)
     .sort((a, b) => a[1] - b[1])
     .map(([id, hours]) => ({
-        label: `UTC${hours > 0 ? '+':''}${('0' + hours).slice(-2)} :: ${id}`,
+        label: makeTimezoneLabel(id, hours),
         value: id,
     }))
 
-export const TimezoneSelect = memo<SelectProps>(({ onChange, ...other }) => {
-    const [id, setId] = useState<keyof typeof rawTimezones | null>(null)
-
-    useEffect(() => onChange?.({
-        timezoneId: id,
-        hours: id ? rawTimezones[id] : 0,
-        isOverride: false,
-    }, []), [id, onChange])
-
-    return (<Select {...other} onChange={setId} value={id} />)
-})
-
 export const makeTimezoneRenderer = () => (timezone?: SimpleTimezoneDto) => {
     if (!timezone) return 'UTC~?? :: Неизвестно'
     const { hours, timezoneId } = timezone
-    return `UTC${hours && hours > 0 ? '+':''}${hours ? ('0' + hours).slice(-2) : '~??'} :: ${timezoneId ?? 'Неизвестно'}`
+    return makeTimezoneLabel(timezoneId, hours)
 }
 
+export type TimezoneSelectProps = OmitExtends<{
+    onChange?: ((value?: SimpleTimezoneDto | null) => void) | null
+    value?: SimpleTimezoneDto | null
+    defaultValue?: SimpleTimezoneDto | null
+}, SelectProps<TimezoneId>>
+
+export const TimezoneSelect = memo<TimezoneSelectProps>(({ onChange, value, defaultValue, ...other }) => {
+    const [id, setId] = useState<TimezoneId | null>(null)
+    const [defaultTimezone, setDefaultTimezone] = useState<TimezoneId | null>(null)
+
+    useEffect(() => setDefaultTimezone(defaultValue ? findTimezoneId(defaultValue) : null), [defaultValue])
+    useEffect(() => setId(value ? findTimezoneId(value) : null), [value])
+
+    const onValueChanged = useCallback((id: TimezoneId | null) => {
+        console.log(id)
+        onChange?.({
+            timezoneId: id,
+            hours: id ? rawTimezones[id] : 0,
+            isOverride: false,
+        })
+    }, [onChange])
+
+    return (<Select {...other} onChange={onValueChanged} value={id} defaultValue={defaultTimezone} />)
+})
+
 export const makeTimezoneColumn = (
     title: ReactNode = 'Зона',
     key: string = 'timezone',
     defaultValue?: SimpleTimezoneDto,
     allowClear: boolean = true,
-    other?: columnPropsOther
+    other?: columnPropsOther,
+    selectOther?: TimezoneSelectProps
 ) => makeColumn(title, key, {
     width: 100,
     editable: true,
     render: makeTimezoneRenderer(),
     input: (
         <TimezoneSelect
+            key={key}
             allowClear={allowClear}
             options={timezoneOptions}
             defaultValue={defaultValue}
+            {...selectOther}
         />
     ),
     ...other
diff --git a/src/utils/datetime.ts b/src/utils/datetime.ts
index b8acfcd..ff39581 100644
--- a/src/utils/datetime.ts
+++ b/src/utils/datetime.ts
@@ -1,5 +1,7 @@
 import moment from 'moment'
 
+import { SimpleTimezoneDto } from '@api'
+
 export type RawDate = number | string | Date
 
 export const defaultFormat: string = 'YYYY.MM.DD HH:mm'
@@ -38,7 +40,40 @@ export const periodToString = (time?: number) => {
     return `${days > 0 ? days : ''} ${toFixed(hours)}:${toFixed(minutes)}:${toFixed(seconds)}`
 }
 
-export const calcDuration = (start: RawDate, end: RawDate) => {
+export const calcDuration = (start: unknown, end: unknown) => {
     if (!isRawDate(start) || !isRawDate(end)) return
     return (+new Date(end) - +new Date(start)) * timeInS.millisecond / timeInS.day
 }
+
+export const fractionalSum = (date: unknown, value: number, type: keyof typeof timeInS): RawDate => {
+    if (!isRawDate(date) || !timeInS[type] || isNaN(value ?? NaN)) return NaN
+    const d = new Date(date)
+    d.setMilliseconds(d.getMilliseconds() + value * timeInS[type] * 1000)
+    return d
+}
+
+export const rawTimezones = {
+    'Калининград': 2,
+    'Москва': 3,
+    'Самара': 4,
+    'Екатеринбург': 5,
+    'Омск': 6,
+    'Красноярск': 7,
+    'Новосибирск': 7,
+    'Иркутск': 8,
+    'Чита': 9,
+    'Владивосток': 10,
+    'Магадан': 11,
+    'Южно-Сахалинск': 11,
+    'Среднеколымск': 11,
+    'Анадырь': 12,
+    'Петропавловск-Камчатский': 12,
+}
+
+export type TimezoneId = keyof typeof rawTimezones
+
+export const isTimezoneId = (value: unknown): value is TimezoneId => !!value && String(value) in rawTimezones
+
+export const findTimezoneId = (value: SimpleTimezoneDto): TimezoneId =>
+    (isTimezoneId(value.timezoneId) && value.timezoneId) ||
+    (Object.keys(rawTimezones) as TimezoneId[]).find(id => rawTimezones[id] === value.hours) as TimezoneId