A "blitz" intended to hasten the arrival of privately sponsored Syrian refugees amid complaints from Canadians exasperated with long delays, ended last Friday with thousands of arrivals still months away.

Immigration, Refugees and Citizenship Canada said it was sending over 40 additional staff to the Middle East on May 9 to finalize applications for privately sponsored refugees for a period of seven weeks. The staffing boost was not extended as some private sponsors had hoped, instead it ended a week earlier than expected.

"The additional staff dedicated to the processing 'blitz' completed their work on June 17," said Nancy Caron, an immigration spokeswoman in an email to CBC News.

"Permanent mission staff in the Middle East are continuing to process private sponsorship applications and finalize cases when ready," she said.

The news that immigration staff have left the Middle East comes after a notice was posted on a government web site Wednesday updating Canadian sponsors on progress made.

"By June 20, nearly 6,100 interviews of privately sponsored refugees have been completed," said the government notice dated June 22. "These refugees will continue through the screening process overseas, which includes full health and security screening."

"It will take approximately three to six months from the interview for refugees to complete the rest of the process and arrive in Canada," the notice went on to say. "Some families are already arriving and others will continue to arrive over the coming months."

The federal government maintains that "every effort" will be made to finish processing all applications for privately sponsored Syrian refugees submitted up to March 31, by the end of 2016 or early 2017.

Charter flights to clear refugee backlog?

Approximately 12,000 Syrian privately sponsored refugee applications were received by the end of March this year, including more than 4,000 from sponsors in Quebec.

John Sewell, the former Toronto mayor who has become a spokesman for private sponsors in Ontario, is calling on the Liberals to use chartered and military planes to clear the refugee backlog.

"Their departure will slow the system further," Sewell said of the "very modest" boost to staff, in an email to members of Canada4Refugees, the national group he helped form.

Doug Earl, another member of the group, said the government should ensure Syrian families and their children arrive before the new school year.

"For that to happen, they need to be moved now," Earl said in the same email.

"Chartering planes would cost, per passenger, an amount comparable to booking individual seats on commercial airliners."

Private sponsors say charter flights would cost the government some $3 million but free up an estimated $24 million in charitable donations sitting in accounts waiting to help resettle these families.

Sewell said it's money that would flow back into the Canadian economy.

"They'll get all the money back, it's just a matter of doing it," he said in a phone interview with CBC Friday.

Sewell said his group will continue to apply pressure on the federal government to act.

According to the government notice, any Syrian sponsorship applications received on or after April 1 will be processed in late 2016 or 2017.

"Sponsors should expect processing times for these applications to be longer," the notice said.

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