In the last shot of Dr. Lee explaining the relay, you can see the drawing of the Daedalus now has an "R" drawn under it that was not there in the previous shot.
This time, it is Sheppard calling the Atlantis star system "the solar system." (The solar system is the one with Earth and The Sun in it. Other such groups are 'star systems', strictly speaking.)
When Dr. Lee is speaking about relaying a transmission to Atlantis, he incorrectly draws the Stargate symbol for Earth on the leftmost part of the white board and identifies it as Atlantis.
While that symbol Dr. Lee uses for Atlantis might be the same one used for Earth, it is also the same symbol used in all of the Stargate Atlantis promo material.