I honestly thought for the longest time that Heather was the Flying gym leader considering we knew that she had a Salamence. But since Ciel (is that her name?) is stated to be the flying gym leader and Saphira is the dragon leader, I'm not so sure what her position in Reborn is. It could very well be an Elite 4 member.
As for Anna, we know her ace is a Gothitelle, but nothing is stated that she is a gym leader. Considering we have already faced the Psychic gym leader and Gothitelle is a pure Psychic Pokemon, she can't be a gym leader. An Elite 4 member, very possible. I mean, if she continues the trend that Noel did (Nomos being Clefable and Nostra being Jirachi), she could very well be an E4 member if she does have a Jirachi.