Commissary Lane already empties into Grand Ave which is the main entrance. So, the only real possible 3rd entrance would be at the end of Pixar. I showed that on the map below in a cyan arrow.
That large green space is a possible expansion pad. Which means, OTOH, that it's cutting into expansion space. But, OTOH, an expansion there can allow folks to pass it by to get in and out of the land. An entrance there means that people exiting TSMM can easily pop into SWGE rather than snake back around the ride building into TSL. It also means they can open Pixar Lane for food carts and M&Gs.
Jim Hill is the only person with this news that I know of.
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