After 32 years of working together, Cromwell and Alexandra are splitting into separate St John area committees.
The growth of the district was behind the restructuring, St John Vincent area committee chairwoman Susan Dickie, of Cromwell, said.
Speaking at the area's annual awards function in Cromwell at the weekend, Mrs Dickie said the change was really a transition rather than a "divorce".
"The two towns have grown so much, to do them justice, we need to have our own area committees.
That way, we can concentrate our energies into our own communities," she said.
As from July this year, the Vincent area committee will cease to exist and will be replaced by two area committees - Alexandra and Cromwell.
"We'll continue to work together but will be separate entities, with different focuses," Mrs Dickie said.
The district's involvement with St John began in 1934 in Alexandra.
The Vincent sub-area, which included Cromwell, was established in 1978.
St John regional trust board member Pauline Beattie, of the Maniototo, said the Vincent area had "grown up and matured" and it was time for separate area committees.
The regional board supported the restructuring.
She congratulated all those who had served the area.
Peter Kircher, of Cromwell, was "blown away" by being made a life member of the organisation.
He started with St John as a volunteer ambulance driver in 1986.
He continued in that role for 15 years and also served in the organisation's community service division and on the area committee's executive.
Mr Kircher was chairman for six years and in 1997 was made a serving brother of St John.
"I feel very privileged to receive this life membership award - in fact, I'm blown away by the whole thing," he said.
Although he was no longer active in St John, Mr Kircher thought the split was a good move and he was considering "putting my hand up again" for the Cromwell committee.
A special award was made to Linda Stephen, of Alexandra, who was retiring from full-time work for the organisation, after serving for more than 33 years.
Other awards presented: 22 years' service, Tania Milne (Alexandra) and Peter Drinnan (Cromwell); 12 years, Peter Kitto (Alexandra); nine years, Paula Dixon (Cromwell) and Brent Wilson (Alexandra); six years, Ashleigh McLellan (Alexandra) and Carol Young (Cromwell); three years, Alaine Kennedy, Alex Taylor, Carolina Merrilees, Jeff Haig, Robyn McDowell, Laurie Stanton and Rebecca Barrow (Cromwell), Melanie Hall (Alexandra).
Ambulance qualifications: Kim Marsh and Kate Little (both Alexandra volunteers).