Maybe a bug in Toybox.Weather in SDK4.2.1 or higher

I found a weird behavior in Toybox.Weather module.

According to the instruction below, return type of Dailyforecast.highTemperature is Time.Moment.

https://developer.garmin.com/connect-iq/api-docs/Toybox/Weather/DailyForecast.html

On the other hand, lowTemperature is Lang.Number.

In the program, highTemperature works as Time.Moment and

it causes an error for my app.

This occurs from SDK4.2.1 and higer.

I mean highTemperature is regrded as Lang.Number in SDK4.1.7 or lower.

Is this a bug?