No. She may not perform the assignment until the petition has been approved and she has been admitted in that status. Work done in advance, including productive work performed during a visit made in another capacity, creates a problem that no later approval repairs.
The commissioning schedule has to bend to the filing, not the reverse
American operations building a new facility set commissioning dates first and ask about immigration second, which produces pressure to have Solveig on site early to advise the contractors. That pressure should be resisted, and the alternative is usually straightforward: she can support the build from Victoria County, on the Canadian payroll, while the petition is pending, and the group should record that this is what she is doing. Work backwards from the date the warehouse must fill its first casks, allowing several weeks to assemble the exhibits, then the adjudication period, then a margin in case further evidence is requested, since responding stops the clock on any expedited processing.
Her qualifying year abroad has to be complete on the filing date. As a Canadian citizen she needs no visa stamp, and the approval notice is presented at the port of entry.