Recently I have played Yellow Submarine and The Last Waltz in DD 5.1. On the movie title or credits it notes DTS. But DTS is not available from the menus or featured on the box. Is there an Easter Egg for DTS or another version with DTS coming?
The movie credits have nothing to do with the disc features. They only indicate that theatrical prints were released with DTS. These days, that's true of most features. It doesn't mean that the disc will have a DTS track. The discs of Yellow Submarine and The Last Waltz do not.
If a disc has a DTS track, you can be pretty certain it will be listed on the box cover.
M.