Cumberland had been coaching in Japan for three years before he was asked to return to the Highlanders last year and work as the scrum coach for the season.
He had previously worked with the Highlanders under coaches Glenn Moore and Greg Cooper but had left to coach in Japan in 2008.
But Highlanders head coach Jamie Joseph had got him back to New Zealand to work as the scrum coach for the franchise and do some work with the forwards. He also helped out on the field during games, relaying messages.
Last week, though, former All Black prop Kees Meeuws was unveiled as the new scrum coach for the Highlanders, with no sign of Cumberland.
Cumberland told the Otago Daily Times it was entirely his decision to leave the Highlanders and move back to Japan to coach.
"I want to be very clear no-one should read anything into my resigning from the Highlanders. It was purely based on me wanting to coach the full Monty rather than just scrums and have more quality time with my family when I'm at home," he said, in an email to the paper.
"I was humbled and at the same time honoured to be asked to join the Highlanders by Jamie [Joseph]. I really thought my time with the Highlanders had finished, so it was a real surprise to be asked and I loved every minute I was involved."
He was back coaching at Kobe Steel.
He said there was simply no foundation to the suggestion he had been pushed out of the role or had a falling out with anyone in the organisation.
Cumberland, who played 81 games for Otago, from 1988-93, said the management team, led by Joseph and Highlanders general manager Roger Clark, had worked exceedingly hard to turn the organisation around and was creating something special.
He had no issue with player selection and had plenty of confidence in his replacement, Meeuws.
"As for my replacement while he may be short on coaching experience, he brings a wealth of playing experience. As Jamie quite rightly said, Kees is a significant appointment. I know he'll go great guns."
The Japanese rugby season is light compared with other countries - about 15 games a year - so that will enable Cumberland more time to get back home to see his family. His partner and two children still live in Dunedin, and did so when he was previously in Japan.
