Change prior_notice_last_time/prior_notice_start_time to (conditionally) optional fields

[westontrillium]

prior_notice_last_time/prior_notice_start_time should not be conditionally required fields. There are cases in which a service has defined earliest/last days but unknown or undefined earliest/last times.

[tsherlockcraig]

And the assumption would be that if prior_notice_last_time is not filled, it's just assumed by consumer to be 24:00:00? I think we'd have to state that. And maybe we want to require the producer to just include 24:00:00 because that's not too tough and it removes the need for the exception?

[westontrillium]

Hmm, I agree it's not a heavy lift on the producer side, but:

1. Does a consumer need the start/last_time defined to understand that a prior_notice window without specific times refers to any trip query within a 24 hour day? I'm thinking that the logic "if search query is submitted after [date that matches prior_notice_start_day], X trip is valid" doesn't also need "...at 00:00:00..." since a date implies any time on that date... Does that make sense?

2. Are there risks in explicitly defining a start/last time when it's technically unknown? e.g., couldn't defining the start/last_time fields in this way potentially give a user false confidence that they still had time to book at an unlikely time like 23:55:00 when the specific timeframe that they can book within a day is actually undefined?

Maybe my second point doesn't matter so much if these fields are more for defining behavior of what trips will show up based on when the user submits a query rather than when they can actually transact with the agency to book...?

[tsherlockcraig]

1. Does a consumer need the start/last_time defined to understand that a prior_notice window without specific times refers to any trip query within a 24 hour day?

I think yes, they do. The 24-hour day isn't really a stable thing in GTFS.

I think the current state of the spec in this regard should remain. The point of these fields is to make unambiguous when trips are allowed when prior_day_first/last_day are defined. The structure of requiring them when those fields are used is tailored and to the point.

[westontrillium]

Agree with keeping current requirement. See my comment here

Closing this PR.