Incorrect date for Bettagsmontag in Swiss Vaud canton region (CH-VD)

[baspeti]

In Vaud canton of Switzerland the Bettagsmontag should be on 2026 September 21st. The API currently reports 2026 September 20th instead, which is a Sunday, and not correct.

This is the curl I used:

curl -X 'GET' \
  'https://openholidaysapi.org/PublicHolidays?countryIsoCode=CH&validFrom=2026-01-01&validTo=2026-12-31&subdivisionCode=CH-VD' \
  -H 'accept: application/json'

And here is the corresponding part of the API response:

...
  {
    "id": "6316c566-9063-4447-a7b0-8c2b69def05d",
    "startDate": "2026-09-20",
    "endDate": "2026-09-20",
    "type": "Public",
    "name": [
      {
        "language": "DE",
        "text": "Bettagsmontag"
      },
      {
        "language": "FR",
        "text": "Lundi du Jeûne"
      },
      {
        "language": "IT",
        "text": "Lunedì di Quaresima"
      },
      {
        "language": "EN",
        "text": "Fast Monday"
      }
    ],
    "regionalScope": "Regional",
    "temporalScope": "FullDay",
    "nationwide": false,
    "subdivisions": [
      {
        "code": "CH-VD",
        "shortName": "VD"
      }
    ]
  },
...