The Silph Raod has always been there for us when in need. This time they may have found a new encounter item within the source code.
“This could be nothing (as all these ‘Ambiguous’ findings could be this round) but something was either re-written or added in regards to wild encounter items. It may be as simple as a backend restructure of the screen where you select a berry/ball, or it may hint to future additional functionality in wild encounters.”- The Silph Team
It’s uncertain with what this “item” could be if there a new one coming for encounters. It’s possible Niantic is adding a new type of ball or berry. There were a total of eight new Pokeballs added into the game when second generation came out, and a total of ten new berries added.
It’s unlikely that new berries will be added, at least for using while trying to catch an encountered Pokemon. The Razz berry was added to the game in third generation, probably because it didn’t have an effect.
More information about New Poke Balls on Page 2