Kitsu Schedule Interface "Invalid date" Error

[Magasul]

When using the Schedule view's "Assign Tasks" panel, clicking Apply results in a 400 BAD REQUEST. The frontend correctly calculates the start date and total estimation minutes, but fails to generate a valid timestamp for the due_date, sending the literal string "Invalid date" to the server instead.

Studio name: Freelancer
Kitsu version: 1.0.20
Production type: Any

Technical Details:

• Endpoint: PUT /api/data/tasks/[task-id]
• Payload Example:

JSON

{
  "estimation": 7680, 
  "start_date": "2026-04-13", 
  "due_date": "Invalid date"
}

• Server Error:

Plaintext

sqlalchemy.exc.DataError: (psycopg.errors.InvalidDatetimeFormat) 
invalid input syntax for type timestamp: "Invalid date"
[SQL: UPDATE task SET estimation=%(estimation)s, start_date=%(start_date)s::TIMESTAMP, 
due_date=%(due_date)s::TIMESTAMP ... ]

• Frontend Error: TypeError at ProductionSchedule.vue:1134 (likely occurring when the UI tries to render the broken date bar).

Observed Math Logic:
The estimation values (5760, 2880, 7680) show that the engine is correctly calculating Total Labor Minutes (Days × Working Hours × 60m × Personnel Count).

• Example: 6 working days × 16 labor hours (2 people) × 60m = 5760 minutes.
• The math is correct, but the Calendar Mapping fails to produce a due_date.

Database Findings:

• Upon inspection of the self-hosted instance:
• The organisation and studio tables are missing explicit columns for monday...friday.
• The working_day table does not exist.
• The project.data JSONB field appears to be missing a working_days array.
• Hypothesis: The JS scheduler crashes because it cannot find the "Working Days" definition in the project/studio metadata to anchor the calculated minutes to the calendar.

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If applicable, add screenshots to help explain your problem.

Desktop (please complete the following information):

• OS: Ubuntu (Dockerized Kitsu/Zou)
• Browser Edge (English language preferred)
• Version Version 146.0.3856.84 (Official build) (64-bit)
• Locale: Hungary (CET)
• Date Context

assignBug.mp4

: Testing with April 2026 dates. Format YYYY-MM-DD