Record the commercial start and end, petition validity, admission period and relevant earlier U.S. stays. Preserve the actual documents supporting each date.
Do not merge different clocks into one
A projected project end does not extend an admission, and a general category maximum does not describe the period currently granted. Have discrepancies reviewed before using the dates in travel or work plans.
A common failure is a group that reorganised years ago and never updated the register, so the corporate lawyer's summary and the filed record describe different companies.
For each transferee, document one continuous qualifying year abroad within the three years that matter; for a new-office L-1A petition, that year itself must have been managerial or executive. A single master timeline consolidating petition validity, each period of admission or extension and any travel that interrupted continuous presence gives one place to check rather than several scattered filings that must be reconciled by memory. Whoever compiles it should verify each entry against the actual stamped admission record rather than a calendar reminder or an assistant's note, since a reminder reflects what someone expected rather than what was actually granted. A renewal prepared from a remembered date rather than the underlying document risks missing the true expiration, particularly where an earlier extension was shorter or longer than the standard period requested. Recording which document each date came from, not only the date itself, makes a later correction easier to trace.