Last refresh Time

You need to create a date in Power Query and pull that in. See this M code.

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("VZDLCQAhDAV78Sxonv9axP7bWLNPMN4mDMYhc7oUBAFRmvNOJBTy8r8RnTpNJh8TdRo0iUzT94BIIeTzRBdAaBr5GF0A0FTyMZqGdNM2mwDkG7CZZuhQKEA2ZdWI+pQ1U9ae/7v5v9vTYNzTYNiyFG/Z5rU+", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [dtDSTStart = _t, dtDSTEnd = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"dtDSTStart", type date}, {"dtDSTEnd", type date}}),
    varCurrentDate = DateTime.Date(DateTimeZone.SwitchZone(DateTimeZone.LocalNow(),-8)),
    #"Filtered Rows" = Table.SelectRows(#"Changed Type", each [dtDSTStart] < varCurrentDate and [dtDSTEnd] > varCurrentDate),
    varDSTOffset = Table.RowCount(#"Filtered Rows"),
    #"Last Refresh Date" = #table(
        type table
            [
                #"RefreshDate"=datetimezone
            ],
        {
            {DateTimeZone.SwitchZone(DateTimeZone.LocalNow(),-8 + varDSTOffset,0)}
        }
        )
in
    #"Last Refresh Date"

That will return a single field with a date. You need to edit the SOURCE row (hit the gear icon) to modify the Daylight Savings Times to your calendar. You also need to modify the -8 offset for the timezone to match your timezone offset to UTC.

Then just create a measure in DAX that would be something like this:

Last Update = "Last Update on " & UNICHAR(10) & FORMAT(MAX('Refresh Time Stamp'[RefreshDate]),"MMM DD, YYYY H:MM AM/PM")

The UNICHAR puts a line break in and shows it on two rows You can remove that.

Note that this will not get the correct hour during the actual DST switch to on/off. I didn't take it that far. It will be correct though after 2am/3am of those days.

1) In Power Query, select New Source, then Blank Query
2) On the Home ribbon, select "Advanced Editor" button
3) Remove everything you see, then paste the M code I've given you in that box.
4) Press Done
5) See this article if you need help using this M code in your model.