BPW 320, a hymn I don't think I have ever sung.  Orignally Greek and old enough to be out of copyright:

The King shall come when morning dawns
and light triumphant breaks,
when beauty gilds the eastern hills
and life to joy awakes.

Not as of old a little child,
to bear and fight and die,
but crowned with glory like the sun
that lights the morning sky.

O brighter than the rising morn
when he, victorious, rose,
and left the lonesome place of death,
despite the rage of foes.

O brighter than the glorious morn
shall this fair morning be,
when Christ our King in beauty comes,
and we his face shall see!

The King shall come when morning dawns
and light and beauty brings;
'Hail, Christ the Lord! your people pray,
'Come quickly, King of kings!'

John Brownlie (1857-1925) from Anonymous Greek

This hymn expresses the more traditional, eschatological view of Advent -  focussing on the second coming, the great consummation, the end of time.

Of course, if we take Jesus at his word, no one can predict what time of day this will take place any more than the precise date it will occur.  I have to confess, I am minded towards seeing it as coterminus with the natural end of all things, though as a teenager had a somewhat stupid fascination with the idea of the 'rapture' and regularly asked God to delay it until I could just do x or y that I wanted to achieve first.

Perhaps what I like about the 'dawn' metaphor in this hymn, emerging from a northern hemipsphere context where dawn is a fairly leisurely process (contra equatorial regions where, I am told, it is near instantaneous) is the idea that this is no 'zap pow' arrival, but something glimpsed as darkness slowly shifts into light; something that becomes clearer and nearer and more wonderful as the light increases.

The phrase (it's strictly two words in Aramaic) "Maranatha" is both a please, "Come, Lord" and a promise "the Lord is coming".  In this hymn, I see more of the second, a hopeful yearning for the completion of a process already began.  The King will come when morning dawns... a process already begun and moving gently, imperceptibly to its fulfilment in the brightness of day.

To my surprise there are many videos of this hymn, among which is this gentle choir and orchestra version: