I haven't seen the 16mm scope yet, currently downloading a 720p version, but it seems very likely that this is the same cut of the film as your other 16mm print, SilverWook. Which means that it's not the original 1971 release cut. The runtime and extended SEN scene suggest so.
If the 35mm re-release prints match the 16mm versions, it means that Lucas tinkered with the film for its home video debut in 1982.