No date can be promised. Official material describes the process in terms of weeks, but that is a description rather than a guarantee, and the final step depends on visa availability under EB-1 or EB-2 as well as vetting, interview scheduling, and any request for further documents.
Keep commitments reversible
Plan the personal side so that nothing irreversible depends on an assumed approval date. Avoid resigning, selling a home, or signing a U.S. lease before the status that permits the move actually exists.
Set internal checkpoints instead — application filed, documents requested, vetting concluded, gift instruction received — and review the household plan at each one. If a school year or a business handover forces a fixed date, say so early and plan around a slip. Attach a decision to each checkpoint rather than only a date.
When documents are requested, confirm that nothing in the personal record has changed. At the vetting stage, confirm the funds remain available in the form previously described. Before any payment instruction, take fresh tax advice if an asset has been sold in the interim.
Hypothetical example: a retired laboratory-animal veterinarian sells a property midway through the process, and because a review was already scheduled at that checkpoint the tax consequence is examined before the payment instead of surfacing in a later filing season.