There undoubtedly already are 'absent Canadians' voting in your riding - as long as they lived there before leaving the country.

That would be people in the first 5 years of their absence from Canada. And any Canadian employed overseas in government work or international NGOs.

The new legislation extends that number, in accordance with section 3 of the Charter of Rights and Freedoms: 
"Every citizen of Canada has the right to vote in an election of members of the House of Commons or of a legislative assembly..."