MOST of us rushing for appointments in Wan Chai of an evening have given up trying to see the time by glancing at Central Plaza's confusing colour-coded timepiece at the pinnacle. Working out the time on a mariner's compass using the positioning of the stars is a damn sight easier. Now comes help from New Zealand Consul-General Don Greenfield. For there he was observing the clock from his place on the Peak over a period of time and, eureka, it came to him. It's all down to the acronym, Greenfield told Keeping Posted. He explains: ''Rhythm and blues pop group - it's as simple as that. Just remember the first initials RBPOPG - standing for red, blue, purple, orange, pink, green. That's the sequence in which the colours appear from 6 pm to 11 pm and then from 12 pm to 5 am''. Simple as looking at your wrist, eh?