Before the petition is drafted, and ideally before the assignment is announced. The year must be one continuous year of qualifying employment abroad within the three years immediately preceding the filing, and gaps, contractor periods or a change of duties can break it in ways that are difficult to repair afterwards.
Verify the year first, because everything else is built on it
Sequence matters more here than speed. The group should start by confirming, from payroll and employment agreements, that Bertrand was employed by a qualifying entity for a full continuous year inside the last three, and that the duties during that year were of the kind being claimed. Only then is it worth investing in charts, letters and corporate evidence.
Two facts commonly interrupt the year without anyone noticing: a period during which he invoiced the group through his own company, and a stretch of unpaid leave. Both should be surfaced now rather than in a request for evidence. Timing also interacts with the property's season.
If the group wants him in place for an opening, work backwards from that date through adjudication, allowing for premium processing if it is used, and for consular scheduling if a visa is needed after approval. Nothing should be committed to staff or suppliers on the strength of an unfiled petition.