Adding further to this. What you heard may have been true, but they might have figured out a good area for Lothal to be placed by the time the episode with the hologram aired. I say this because Lothal's location is already very interesting. It's right next to Yavin 4 so I could very easily see them writing in that the Rebellion is now ballsy enough to have a formal base on Yavin 4 next to Lothal in Season 3.
Another interesting thing is they've said that the Rebellion symbol will turn into the OT symbol when they fight with the Onderon Rebellion from TCW (see pic related). They recently went to Mandalore in Season 3. You could theorize they're going to slowly get closer and closer to Onderon until we see Phoenix Squadron meet the Onderon Rebellion.