You'll animate the type using the powerful Animator features, which are only available for text layersin this case, you'll use the animator to scramble the letters with the Character Offset property:
How does your text look at time 0;00? It should be an unintelligible mess, thanks to the character-offset settings you applied to the layers. With a Character Offset value of 40, the original letters are each replaced by whatever letter exists 40 letters forward alphabetically. For example, 40 letters forward from the letter C is the letter Q. (Since there are only 26 letters in the alphabet, you must start over at letter A once you hit Z, in order to figure out the letter that will display.) If you go time 14;20, where the Character Offset should already be set to 1, you'll see that every letter is only 1 character away from the letters in the original title.
At time 0;14 seconds, Character Offset is 3, so the letters shown are three letters forward from the original title's letters.