cockpitvisit
The ping information released was only from the final 8:11am ping. Info about the earlier pings has not been released although there was apparently some unconfirmed rumour from CNN earlier this morning that the previous ping was from the same distance as the last.
The pings do just give us distance from satellite (based on signal travel time).
Yes, the investigators must have other rings for earlier pings.
The fact that POR and AORE did not hear pings at 8:11am rules out parts of the red circle. Travel distance also helps a little.
That gives two red arcs: north and south.
The plane either went to the north arc or the south one. Thus there are loosely two ``routes''.