Using StopTimeEvent.uncertainty for non-timepoints

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Hi, I'm a developer at AC Transit trying to improve our GTFS-RT feeds.

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My agency only holds timepoints as accurate trip stop times while non-timepoint trip stop times are approximate. This confuses riders as they see buses as sometimes early while that is not really the case. Sometimes a bus might arrive 3+ minutes early then leave but that is within scheduling's accuracy constraints, so people miss the bus (late is obviously less important but equally relevant for non-timepoint transfers for leg changes).

Is it a good practice to populate the uncertainty field when we know the typical spread of the approximation, leaving delay as 0 to cause a +/- seconds in effect?

The closest I found discussing this was:

[Clarify definition of "frequency-based" trips](https://github.com/google/transit/pull/47) and [Add prediction certainty #111](https://github.com/google/transit/pull/111) and my question isn't clearly answered by the current definition @ [message StopTimeEvent](https://gtfs.org/realtime/reference/#message-stoptimeevent).