Jawa77 said:
Nope "Close the blast doors, close the blast doors! .... Open the blast doors, open the blast doors!" was there in the original 70mm Dolby 6 channel on opening day.
"Close the blast doors" was not in the 70mm Dolby 6-track mix.
There are in-theater recordings of the 6-track mix from 1977 that corroborate this fact.