Canada has a TBA for which they can name any Canadian team they submitted to the ISU. Conventional wisdom had Kirkland/Radford and the Moscovitches vying for the final spot in early season competitions.
World ranking is not considered for the replacement spots, unless by some unlikely event those guaranteed 1 spot for being in the 24 top ranking didn't get their one spot in the initial selection process.** Top 75 PB in qualifying competitions are. But there were only 69 ranked PB's from last year, and every pair who competed in one of the qualifying competitions (Worlds, Jr. Worlds, Jr. GPF, GPF, Grand Prix, Euros, 4C's) is eligible for selection, if they are still skating together and their Federation put their names in the selection hopper. Pairs can compete in both juniors and seniors.
I thought, though, that the host nation had to go to the top 75 PB list to replace one of their selections. Neither team is on this list, because last season they didn't compete in senior GP (both girls too young?), and both men were too old for junior GP. Canadian pairs qualifying on the top 75 PB and not already assigned to two events are:
Miller/Moram (retired)-16
Brodeur/Mattatall-20 (They have CoC)
Pisotta/Stewart-30 (They have CoR)
Velanosi/Fernandez-32 (They have CoR)
Lawrence/Sweigers-35
Jones/Jackson-37
Steele/Johnson-44
McCoy/van Cleve-53
But no guarantee that Skate Canada made any pairs but the already assigned eligible for selection.
**I suppose in some alternative universe it would be possible for all of the following to be independent:
*Top 12 from last year's Worlds: 24 guaranteed spots
Top 24 PB: 24 guaranteed spots
Top 24 World Rankings: 24 guaranteed spots
Top 3 at Jr. GP (turning senior): 3 guaranteed spots
Top 3 at Jr. Worlds (turning senior): 3 guaranteed spots
Three selections from host nation: 3 guaranteed spots
Total: 81 guaranteed spots for 48 places