Unexpected Snooze

My out of bed initiative for 7AM has gone mostly well, though with a few unexpected disclosures of my innate sleep cycles.  Middle of the Night Insomnia continues, though the wake time has lost some of its 3AM predictability.  Last night it came closer to 4:30AM, though without as sense of completing my nightly rest.  Ordinarily I would begin to time 10-30 minute intervals with my smart watch, assigning each session uninterrupted time in a fixed position, whether supine or lateral, fully under down comforter or arms exposes.  Alas, my watch's battery had run out.  So I looked at the red numerals on the clock periodically, typically 10-15 minute intervals, as I made the best of my blanket options.  The last time I remember was 5:59AM.  Up in an hour.  At the next update, the clock read 7:15AM.  I had an unexpected 75 minute return to the oblivion of sleep.  Actual OOB time, 7:22AM, feeling mostly good.  That final lap of sleep, stages completely without ability to reconstruct, added to the night's restorative benefit.  Morning routine slightly delayed, but now with newspaper retrieved, indoor herb plants checked, overnight messages reviewed, and some coffee being sipped, that seems to be a very useful 75 minutes.