All the EMI group's labels changed late 66 early 67.
Tamla Motown, Stateside, Verve, Liberty, United Artists, HMV, MGM all changed to green and white.
Verve and MGM only had a few green and whites before both changing to pink and silver.
At the same time, Pye changed from white demo to yellow demo.
I honestly have no idea why this happened.