Yes it should change to we are reviewing the additional documents, but that will change when officer looks into file.
I hope the officer looks into it soon. It is so much of a dilemma as what to do. Booking the flight and then cancelling later is a waste.
I would say book a flight now for April (couple days before the visa expiry date) and also buy the insurance.
Insurance will cost you maybe $100 max but if you get everything done before the expiry date then cancel the flight.