Pippa Middleton has failed to follow through on her plan to enter the Coast to Coast challenge, instead choosing to sun herself on a Caribbean beach.
According to the Daily Mail, Middleton is relaxing in Mustique with the rest of her family, as the Duke and Duchess of Cambridge rent a £19,000-a-week (NZ$35,000) holiday home.
Late last year Middleton boasted of her intentions to enter the gruelling 243 kilometre race in a column in The Spectator.
But she has failed to enter the race, which starts tomorrow.
Middleton's spokesperson failed to answer questions over whether she was injured or just no longer interested.
But Coast to Coast spokesman Michael Jacques told the Mail they'd yet to receive her entry.
"The interest created by Pippa Middleton participating in the Speight's Coast to Coast certainly generated more international interest in the event," he said.
"So we have to thank her for that.
"But unfortunately it has yet to generate an entry from Miss Middleton herself."
The Coast to Coast begins in Greymouth and sees participants race north through the Southern Alps both running and cycling, then kayaking down the Waimakariri River before cycling the rest of the way to Christchurch.
Middleton's post in The Spectator also appears to have been altered, and now no longer holds any mention of taking part in the challenge.
In December last year she wrote: "Another year, another challenge.
"For the last four years, I have given myself a feat to accomplish, from sailing the Atlantic to climbing Mont Blanc. It may sound dauntingly hearty, but really it's just good fun, plus it provides some routine, discipline and fitness.
"Next year I am hoping to do the Coast-to-Coast in New Zealand, which is a triathlon (running, cycling and kayaking) from the South Island to Sumner Beach on the Pacific.
"It's in February, so I'd better hold back on the food and drink, starting now. Happy Christmas everyone."