Simple, every time a new expansion launches you can have a trial for a few days to level up to 1 exp before the previous expansion's level cap, and you can try new zones and class changes, if that's not enough for you good riddance.
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Every expansion has a trial for a few days if you haven't bought it. There are just restrictions, you can't expect them to give you full legion access and you to level to 110 and set up everything for free. If your trust is lost then gtfo.