Plan in months rather than weeks. Incorporating and equipping a U.S. entity, securing premises, assembling corporate evidence and preparing the petition typically take longer than the adjudication that follows.
Most of the delay happens before anything is filed
A realistic sequence for a first transfer runs roughly like this. Incorporate the U.S. entity and open its bank account. Secure premises, because a new-office petition is expected to show them. Assemble corporate evidence from both sides, which usually exposes a missing share register or an unsigned agreement that takes weeks to correct. Draft the position description and the first-year plan, and revise them until they describe a role the company can actually deliver. Only then does the petition go in, and processing time should be checked against current USCIS posted times rather than assumed; premium handling, where available, shortens adjudication but not preparation. Families should also allow time after approval for schooling, housing and the spouse's employment documentation. Six months from decision to start date is not a pessimistic estimate for a company doing this for the first time.
Hypothetical example: A Canadian publisher of language-learning materials plans to transfer its division head to open a U.S. sales office next spring. The company should sequence ownership verification, premises, foreign payroll records, and the one-year operating plan before it chooses a launch date. The employee must have completed the qualifying year abroad during the prior three years, and the U.S. role must be managerial or executive rather than a disguised first sales hire. Board resolutions, a lease, recruiting calendar, and proposed reporting lines provide an early reality check. A delayed premises decision often compresses the rest of the file into a rushed petition. Because L-1A time is limited to seven years, the company should build the staff structure early enough for the executive to direct rather than personally perform the core work.