The Canadian Union of Postal Workers is concerned about changes Canada Post warns could be coming.

In May, the Crown Corporation will start test-sorting Charlottetown mail in Halifax. The move would reduce the amount of work clerks at the depot and postal carriers in Charlottetown need to do.

Canada Post says no permanent changes will made until October, but it's warned the union up to three letter carriers out of 20 delivering in the capital may no longer be needed.

The head of the Charlottetown local, Pearl Gillis-Palmer said Canada Post isn't telling them how the decision will affect clerk staffing levels.

"The only thing that we have so far, is that it looks like there, the letter carriers, their positions will be deleted," she said.

Pearl Gillis-Palmer, Canada Post Charlottetown union president

Gillis-Palmer said the union is also worried letter carriers in Charlottetown could be asked to deliver even more. (CBC)

"And then, down the road, it's going to affect clerks because they don't need them to sort the mail if it's coming already pre-sorted and sequenced for each route."

'No employees will lose their jobs'

In an email statement, Canada Post said if there are changes, any employee affected would be offered other work. 

"We're going to do a sequencing exercise for a few weeks starting in May in order to gather information on how much of the mail our machines can sequence ... We will use this information to make changes to our employees' itineraries in October," said Eugene Knapik, Canada Post Media Relations.

"No employees will lose their jobs. Our customers will not see any significant change in their mail service. Any reduction in the number of positions required will take place through attrition."

Gillis-Palmer said the union is also worried letter carriers in Charlottetown who are already facing long routes could be asked to deliver even more. 

"We're not with this at all. We're trying to fight it," she said.

"The routes in Charlottetown now they're all too large, they're taking too long, and we're going to continue our fight because it's just too hard on the letter carriers. It's too much work for them."

Canada Post said it will be re-evaluating the length of routes in Charlottetown during a two week visit in late May and early June. 

With files from Laura Chapin