Pokémon: Did Dawn Need to Replace May?

In theory, May could have stayed with Ash when he was traveling to the Sinnoh region, but she was ultimately replaced by Dawn. Here

Pokemon Finally Brought Back Missing Fan Favorites for Ash's Big Win

Pokemon Anime Updates Fans on What Dawn Has Been Doing Since Traveling With Ash

How to play Pokémon trading card game: Rules, time duration, setup

Dawn into May by TheSuitKeeper89 -- Fur Affinity [dot] net

Why did the original anime series 'Pokemon' replace the characters of Brock and Misty with Dawn and May, respectively? Did you prefer one over the other, or both equally? Why? - Quora

Pokemon Anime: The Ages, Hometowns, And Known Relatives Of Ash And 9 Of His Companions

Who are Misty, May, and Dawn in Pokemon and why are they important? - Quora

Pokemon Battle USUM: Dawn Vs May (May Vs Dawn Companion Battle)

Pokémon: 25 Things That Don't Make Sense About May

She deserves winning Ash's heart. : r/pokemonanime