The new Elixir system was more than just changing the values, it was a full rewrite to the underlying tech that allowed the game to be more accurate in displaying what was happening. Prior to this update, it would always show 1x/2x Elixir, even if the values weren't exactly accurate.

Rage Mode was always 135% Elixir (your Elixir was Rage'd too!), so now we display the 1x-2x-3x stages as 1.3x - 2.7x - 4x, as that is a more accurate representation of how much Elixir you are generating.