---
id: change/bcapps/11507
type: change
title: "#11507 [Master] Fix Unix timestamp timezone conversion"
summary: Unix timestamp conversion in TypeHelper now delegates to System.DateTime's Unix Timestamp codeunit to avoid incorrectly shifting UTC instants by the user's timezone offset, especially during daylight saving time.
tier: official
language: en
tags:
  - fix
  - main
  - bc30
  - codeunit type helper
system: development
review:
  state: reviewed
  by: opus
  at: "2026-10-08T02:03:56.926Z"
  flags: []
generated:
  at: "2026-10-08T01:26:53.141Z"
  pipeline: 0.2.0
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  input_hash: 5c5cdeff91ad7f92761bf219e29aaae010b3ed57
evidence:
  - kind: code
    url: https://github.com/microsoft/BCApps/pull/11507
    title: "microsoft/BCApps#11507: [Master] Fix Unix timestamp timezone conversion"
    date: "2026-09-23"
    commit: 5c5cdeff91ad7f92761bf219e29aaae010b3ed57
    t: null
    quote: null
links:
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  objects:
    - object/codeunit/10
  features: []
  topics: []
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  posts: []
  guidelines: []
  changes: []
number: 11507
repo: microsoft/BCApps
source_id: bcapps-prs
url: https://github.com/microsoft/BCApps/pull/11507
kind: pr
base_branch: main
major: "30"
merged_at: "2026-09-23T19:51:23Z"
author: haoranpb
author_type: User
community_contribution: false
labels:
  - "Team: Integrations"
change_class: code
change_kind: fix
behavior_change: true
breaking: false
files:
  count: 2
  additions: 52
  deletions: 16
  al: 1
apps:
  - Base Application
objects_touched:
  - key: codeunit/10
    page: codeunit/10
    type: codeunit
    id: 10
    name: Type Helper
    app: Base Application
    status: modified
objects_unjoined: []
obsoletions: []
backports: []
fixes_issues: []
work_items:
  - 650271
systems:
  - development
quote: null
joined_against:
  major: "30"
  commit: ecbc028c25dbe83b61313bc566e6c1d41184bb1c
---

# #11507 [Master] Fix Unix timestamp timezone conversion

> Unix timestamp conversion in TypeHelper now delegates to System.DateTime's Unix Timestamp codeunit to avoid incorrectly shifting UTC instants by the user's timezone offset, especially during daylight saving time.

[Pull request](https://github.com/microsoft/BCApps/pull/11507) · merged into `main` (BC30) on 2026-09-23 by haoranpb · 2 files (+52 -16), 1 AL · fix · tier official · reviewed (checked by Opus)

## What changed

- TypeHelper.EvaluateUnixTimestamp previously added timezone offset when converting Unix timestamps, causing one-hour shifts during summer time
- Conversion now uses System.DateTime's Unix Timestamp codeunit which correctly uses DateTimeOffset.FromUnixTimeSeconds
- Tests verify that the same UTC instant is returned regardless of user timezone (UTC or Central Europe Standard Time)
- Fixes issue where Central European summer time shifted the represented UTC instant by one hour
- Behaviour changes for users or extensions.

## AL objects touched

- [Codeunit 10 "Type Helper"](../../objects/codeunit/10.md), Base Application: modified

## Context

- Work items: AB#650271
- Labels: Team: Integrations
- Systems: development

Source: metadata of a merged pull request in microsoft/BCApps (bcapps): title, labels, changed paths and counts, with a summary in our words. No source text and no description beyond one short quote (D10, D61).