If she had her mind altered like Revan her being dropped on Jakku as a child could be a false memory meaning she only got dropped off there once.
That leads to my second point: Her whole backstory as we know it is a lie, which I’d rather not have, as it’s removing backstory for the sake of having a twist, rather than adding to the plot.
There’s one possibility I didn’t note: an incident which led her to being dropped off when she was five, one separate from the massacre Kylo Ren committed to the Jedi Academy. This could work, if set up right.