How were the 2014 Gamora and OG Nebula able to travel to the present? From the movie, we know that for you need two thing for time travel: Pym particles and Time-Space GPS or the Time Gateway (like Thanos traveling to the present time with his ship and army). But the Time-Space GPS of the original Nebula was clearly seen being taken from her by the 2014 Nebula and she then traveled to the present with it.
Then, after Thanos's attack on the Avengers Compound the OG Nebula and 2014 Gamora also travel back to the present to fight the 2014 Nebula. How were they able to do this without the Time-Space GPS? Did I miss something?