This is what we found on Wikipedia regarding the The Drifters Tribute:

The Shadows (originally known as the Drifters between 1958 and 1959) were an English instrumental rock group, who dominated the British popular music charts in the pre-Beatles era from the late 1950s to the early 1960s. They served as the backing band for Cliff Richard from 1958 to 1968, and have joined him for several reunion tours.

The Shadows had 69 UK chart singles from the 1950s to the 2000s, 35 as the Shadows and 34 as Cliff Richard and the Shadows, ranging from pop, rock, surf rock and ballads with a jazz influence. The group, who were in the forefront of the UK beat-group boom, were the first backing band to emerge as stars.

As pioneers of the four-member instrumental format, the band consisted of lead guitar, rhythm guitar, bass guitar and drums. The Shadows built their signature sound on Fender guitars and Vox amplifiers, but around 1964, they replaced their Fenders with Burns guitars, with Bruce Welch citing tuning issues as the main reason.

The core members from 1958 to the present are guitarists Hank Marvin and Bruce Welch and drummer Brian Bennett (who has been with the group since 1961) with various bassists and occasionally keyboardists through the years.