# Schedule mutations

**Authentication:** legacy `X-Dyflexis-AuthToken` header (see the *Legacy v0 token* security scheme), not `Authorization`.
> **Legacy**, Kept for existing Business Intelligence consumers. Avoid for new integrations; there is no v3 equivalent yet.

Returns a list of changes in the schedule for the specified period, limits to 500 a page.

Endpoint: GET /api/v0/mutation
Security: XDyflexisAuthToken

## Query parameters:

  - `month` (integer)
    Required integer in the following range 1 <= integer <= 12

  - `year` (integer)
    Required integer in the following range 1 <= integer

  - `page` (integer)
    Page number of the paginated result set. The first page is `1`.

## Response 200 fields (application/json):

  - `api` (object)
    Metadata about the API call (server time, request timing, etc.).

  - `response` (object)

  - `response.data` (array | null)
    The schedule mutation records, or null on error.

  - `response.expires` (string)
    Timestamp after which the response is considered stale.

  - `error` (string | null)
    Error message, or null on success. Authentication and other failures
are returned as HTTP 200 with this field populated (for example
`Invalid auth-token`); this endpoint does not use 4xx status codes.