Work backward from the intended transfer through evidence collection, petition review, any required visa processing and admission. No single published processing figure covers all of those stages or guarantees a start date.
Keep validity separate from processing
Confirm current government processing information for the actual route. Where available, premium processing purchases an adjudicative response within its applicable service period, not guaranteed approval or completed travel. A new-office approval period is limited to one year, while established-office and later requests follow their own validity rules.
Record admission and petition dates separately so the extension plan uses the correct deadlines. Calendars slip because the critical path runs through people who do not report to the case owner. Hypothetical example: A trade-finance advisory firm sets a transfer date around a client mandate, but the foreign payroll extract needed to evidence the qualifying year sits with a finance manager in another country who has no visibility of the deadline.
Tell each contributor their own due date and what happens downstream if it moves, rather than circulating one distant target. Separate the dates you control — drafting, internal review, signature — from the dates you do not, which include adjudication and any consular step. Someone should also own the post-arrival calendar, because the person who tracks the extension deadline is frequently not the person who tracked the filing.