The Senate was set to resume special debate Monday afternoon (2 p.m. ET) on back-to-work legislation that was introduced by the Trudeau Liberals and passed Friday in the House of Commons.
Dodsworth said the tone of negotiations changed when the government hinted two weeks ago that it would consider back-to-work legislation.
Members of the Canadian Union of Postal Workers (CUPW) staged protests against the legislation across the country Tuesday morning.
However, the legislation could be delayed by a number of factors, such as amendments.
"We're relieved to see Canada Post back to work and hope the corporation and the union can reach a long-lasting agreement to ensure Canada Post can become a low-priced and reliable option for small business", said Dan Kelly, president of the Canadian Federation of Independent Business.
Negotiations have been underway for almost a year but the dispute escalated when CUPW members launched rotating strikes October 22.
Canada Post said Tuesday that it could not live up to its normal delivery standards through the remainder of the year, and going into January 2019, as a result of backlogs of mail and parcel deliveries at its main sorting plants in Vancouver, Toronto and Montreal.
"It's not the work, it's the work Canada Post is putting on its workers".
"International items will require screening by the Canada Border Services Agency and we are working in partnership with them to manage the significant existing backlog".
CUPW's 50,000 members, in two groups, are demanding better pay for rural and suburban carriers, as well as greater job security and minimum guaranteed hours.
After 37 days of rotating strikes, he says they have not given up the struggle to reach collective agreements.
"Obviously the Senate has done the work that they need to do and the legislation has passed", Hajdu said. "This law violates our right to free collective bargaining under the Charter of Rights and Freedoms".
The union is to decide this week how to fight back if the bill becomes law, with its national president, Mike Palecek, saying all options are on the table.
The Canadian Union of Postal Workers maintains the legislation is unconstitutional and has vowed to challenge it in court.
But the Liberal government argues its bill is different, in that it does not impose immediate new contracts.
The legislation would give a mediator-arbitrator appointed by the government 90 days to try and reach contract settlements. Failing that, a settlement could be imposed either through a decision from the arbitrator or by choosing from one of the final proposals put forward by Canada Post and CUPW. Canada Post says unprecedented backlogs will continue to mean lengthy delays for customers dropping parcels and letters in the mail.
Parcel delivery volumes are normally in the range of 500,000 packages on late November weekends, said Jon Hamilton.