Yes, some members of the production are interested in filming The Magician's Nephew next. Partially because it's their favorite story
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and partially because they want to film Tilda in the role of Jadis before she ages too much more.
But there are also a number of production people (like Douglas Gresham) who are adamant about doing The Silver Chair next because otherwise Will Poulter will be in his 50s by the time they get around to doing that movie.
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I strongly suspect that The Silver Chair will easily win out if Will Poulter gets a strong reception in VDT (and he sure did yesterday)! They won't want to lose box office numbers simply because they recast him when they didn't have to.
But as to your concern about skipping to The Last Battle and/or not making any more movies, those rumors are based on theories and what-ifs and nothing more. The production's desire is still to make all seven books into movies. And they have issued this official statement many times.... As long as these movies continue to do well at the box office, they will continue to make them. If VDT tanks (no pun intended) we may see the end of the movies entirely.