When is “fairy time”?

Fairy time occurs shortly after midnight.

The iron tongue of midnight hath told twelve.
Lovers, to bed. 'Tis almost fairy time.
I fear we shall outsleep the coming morn
As much as we this night have overwatched.
This palpable-gross play hath well beguiled
The heavy gait of night. Sweet friends, to bed.
A fortnight hold we this solemnity,
In nightly revels and new jollity.

Which time comeing fairy at night