I had the same experience a few days ago- I sniped it here and did a manual back up snipe since I was at the office. Both hit at the same second. LOL.
And my bid was advanced to the reserve amount. Glad it happened, even though the reserve was high, I wanted the item.
But I saw no other tall bidders and wondered if that is what happened, my bid was advanced to meet the reserve. Guess it seems logical, but I will snipe more carefully at items with ongoing reserves.