A qualifying L spouse’s employment authorization is based on the spouse’s status with appropriate documentation, not on employment in the principal applicant’s division.
Identify each person’s own permission
Confirm the spouse’s qualifying status before relying on work authorization. Children do not obtain work permission solely from L dependent status. A shared employer name does not itself establish any family member’s immigration status.
Separate the two calendars, because they turn on different events. The principal's calendar turns on the petition, the visa where one is required, and admission. The dependent's calendar turns on that person's own admission in L-2 and on the documentation evidencing it; L-2 spouses are generally employment-authorised incident to status, while children obtain no work permission from dependent status.
Hypothetical example: the spouse of a manager transferring from a specialty food-processing plant hands in notice on the strength of an approval notice addressed to the principal, before either of them has been admitted. Notice given cannot be recalled, and an approval notice is not an admission record. The sequence worth holding to is short: the principal's status is established first, the dependent's own status and evidence second, and any employment commitment for the spouse third.
Reversing that list is what produces the gap households later describe as a surprise. Write the two calendars on one sheet with a vertical line between them. Nothing crosses that line without a document behind it.
The habit sounds fussy until a date from the left-hand column is quoted to a landlord as though it belonged on the right.