The 19-year-old University of Otago commerce student and New Zealand rowing representative said he wanted to make the journey in remembrance of his mother Sonia, who died of breast cancer in 2007.
Initially, he planned to begin his journey in early January, but foul weather forced him to postpone it.
He then set a new date to leave tomorrow, but after recently meeting representatives from Dunedin police and MSAR, he was given an "encouraging but cautionary" response to his initiative.
"Basically, they ran me through the risks and how dangerous it really is, based on their knowledge and everything they’ve seen during the rescues they’ve made.
"They said the weather would be better, more stable from the end of March onwards. Heading in towards winter, the weather can become more settled.
"So to make it safer for everyone involved, I’ve decided to wait until the start of April to do it.
"They said something like this is achievable, but it’s also very unachievable — it all comes down to the planning.
"They want me to spend a bit more time going into the nitty-gritty of planning, to make sure I am prepared for absolutely anything.
"The goal isn’t just to row around the South Island. It will be to survive each day.
"I want to achieve the goal, not end up in a box."
As part of his more in-depth planning, he said his father was seeking to buy or borrow a much larger seaworthy boat to take a support crew on the trip.
The row would now start in Otago Harbour in April.
He planned to row up to 50km a day and expected it would take about 50 days to complete the circumnavigation of the island.
"Rowing around the South Island will no doubt have road blocks and seem impossible at times — that’s no different to Mum’s journey with cancer."
Mr Mason hoped to raise about $20,000 to help fund ground-breaking work by some of New Zealand’s top breast cancer researchers, educate people about breast health, and provide free support services for breast cancer patients and their families.
