Translation:The history will have been read tomorrow.
Ahhh... things are a little tricky with passive participles.
There have been great battles throughout the decades between "atistoj" and "itistoj" about which vowel to use in passive participles in which situations. I picked up a whole book on the topic on an Esperanto flea market once: 320 pages full of various essays on -ata/-ita. (I confess I haven't read it.)
I think that the current consensus is that passive participles mark aspect, not tense.
So "legita" means "read" with the expectation that the reading will be finished tomorrow while "estos legata" would be more like "Tomorrow, the reading will be ongoing" (it probably started before tomorrow and will continue until after tomorrow).
I think part of the problem is that both approaches are logical (in their own terms), and both sides have used sentences from the Fundamento in support of their view.
So in the end it's arbitrary, like much of language - you simply have to decide on one without being able to justify the decision with "it's the only logical possibility".
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