It’s well known within industry circles that the plan was to release the OT’s theatrical versions in new 4K transfers prior to ‘The Force Awakens’ but the 1977 film needed a lot more work than initially thought - Disney even went so far as to ask the Library of Congress for a scan of the print they’ve had in their archives since 1978 - and so it was put back until the 40th anniversary in 2017… But we haven’t seen them yet so maybe 2018 to coincide with either Solo: A Star Wars Story or may come after the 4k release of TLJ cause that would kick ass
Please feel free to list sources for these claims.