Flex: forbidden_prior_notice_start_day

[emmambd]

Describe the problem

See below

Describe the new validation rule

forbidden_prior_notice_start_day as defined in the table here

Sample GTFS datasets

No response

Severity

Error

Additional context

No response

[qcdyx]

Tasks:

• [ ] add logic to the forbidden_prior_day validator and add a new notice
• [ ] add tests
• [ ] review auto-generated documentation
• [ ] review acceptance tests