Hundreds of Samaritans volunteers say they will leave the suicide prevention charity if plans to close more than 100 branches are supported at a meeting this weekend.

Some opponents of the changes fear an exodus of staff could put the charity’s ability to answer calls in doubt.

The controversial plans, unveiled in July, would see at least half the Samaritans branches in the UK and Ireland close.

Volunteers would instead work out of larger offices or answer calls from home as the charity moves to embrace a remote working model.

In a statement, the Samaritans said its proposals would mean “we can answer more calls, cut wait times and make it easier for people to volunteer with us”.

If passed, the first branches would begin to close in April in the UK and 2027 in Ireland, with a gradual reduction over the coming decade.

Critics of the plans say the changes will decimate the Samaritans’ work in local communities and have accused the charity’s leadership of repeatedly ignoring requests to provide the rationale for the plans.

Some branches have called for a vote of no confidence in the chairman at a meeting next month.

More than 50 branches, over a quarter of the total, immediately raised concerns when the plans were unveiled and it seems that opposition has only grown.

The list of branches that would close has not been released, but James Watkins fears his one in Rhyl, Denbighshire, would go.

It’s situated in the heart of the town, in one of the most deprived neighbourhoods in Britain, with high levels of mental health problems.

Mr Watkins, 58, says that volunteers are drawn to helping their own community as much as staffing the charity’s nationwide phone line.

The branch’s volunteers, he said, had recently been out at a local college and at the train station raising awareness of their presence.

“All of those things emanate from the fact we have a local branch and would likely go if we closed. Our branch has been going for over 50 years and our connections with our community has grown and grown,” said Mr Watkins.

He’s one of between 40 and 50 volunteers in Rhyl, but after speaking to colleagues said he was not aware that any of them would remain if the branch closed.

Last month, Mr Watkins organised a survey of volunteers across Wales. He says he received a response from 210 people, about one third of all Welsh volunteers.

Three quarters of people who responded said they would not move if their own branch was closed. The same proportion said they would not be interested in remote volunteering.

“With less people, [the Samaritans] are not going to be able to answer as many calls. This is the point we keep making and it seems to be falling on deaf ears. This could be the beginning of the end for the Samaritans.”

The charity’s leadership have called its proposals “future-proofing” and said that having more than 200 branches “is not sustainable and hinders us” from providing the best service.

The Samaritans considers itself the fourth emergency service and estimates that it answers a call every 10 seconds.

Despite the controversy, the charity insists it will continue to be there “for those struggling to cope across the UK and Ireland, day and night, 365 days a year”.

The proposals, say the charity, are intended to increase the number of volunteers, including by introducing remote working.

“That’s a red herring,” said Mark Watkins, a volunteer on the Isle of Wight for the past 17 years.

He points out that remote working has not been properly piloted, and describes as “airy fairy” plans to source more volunteers.

He doesn’t believe that any of his branch’s 65 volunteers would remain if the Isle of Wight branch were to close.

“If you’re alone in your house at 03:00 and you are taking a call that we would characterise as suicide in progress, you have no shift buddy there to support you – that has never happened in the 70 years of the Samaritans. Callers have a right to be concerned,” said Mark Watkins.

The Samaritans say that remote volunteering is currently being piloted and if it is approved, it would only be an option alongside working in a branch.

While the plans have been open to consultation, branch directors and volunteers from the north of Scotland to the south of England have told the BBC that they’ve not been listened to.

“There is a lot of despair and disillusionment,” said Colm Martin, who has been volunteering at London’s Kingston branch for five years.

“There has been no listening which is ironic for a charity that’s all about listening.”

Mr Martin has been a vocal critic of the proposals and says there is distrust of initiatives from Samaritans’ management after an app had to be closed down and a new internal email system had proven hugely problematic.

“They have provided no evidence for these changes [to branches]. They have a ready-made focus group [thousands of volunteers] – they could have asked us what we think.”

Such is the anger that a letter signed by seven branch directors has been sent to the trustees of the Samaritans calling for the chairman Keith Leslie to be removed at a meeting in late October.

“We do not feel these concerns are being fully heard, and we fear that implementation of the current in-principle decisions could seriously harm and diminish the organisation,” they write.

Almost 150 branches are independent organisations, responsible for all their fundraising locally and receiving little, if any, financial support from the charity’s headquarters.

Some have been gifted offices free of charge by local organisations, but if those branches were to close, the charity’s headquarters would benefit from any sale of the premises, adding another layer of unhappiness for many volunteers.

“We have been listening to feedback from our 23,000 volunteers throughout this process and this will be considered carefully in the final decision making,” said the charity’s chief executive in a statement.

“Samaritans’ life-saving work is needed now more than ever but I’m confident that by everyone pulling together for our beneficiaries and callers, our service will be stronger and better prepared than ever before to meet the challenges of the future.”

If you are suffering distress or despair, details of help and support in the UK are available at BBC’s Action Line.