Until 1972 sound recordings were in the public domain. The entire released Beatles oevre is in the public domain. The 1972 revision of Title 17 created protection for sound recordings and the "P-in-a-circle" copyright symbol for "phonorecords."

You could technically release the Beatles albums legally if you made the new records off of the original vinyl records and made it very, very clear that the releases were not authorized. Of course, the attorneys for the Beatles would keep you busy with various spurious complaints, but if you stuck with it and financed your defense, in the end you would win.