No. The official page does not fix a timeline, and vetting, the underlying employment-based petition and visa availability all affect timing. Irreversible steps such as a home sale should wait until residence is actually granted or at least until the process gives a concrete stage.
Keep the irreversible steps behind the official process
Hypothetical example: the couple are tempted to list their house so the gift funds are ready. The official framework describes an application with a nonrefundable processing fee, vetting, and a gift requested after successful vetting, followed by EB-1 or EB-2 processing subject to visa availability; none of that guarantees a fixed date. The vetting stage has no published duration, the petition stage follows processing times, and visa availability depends on the category and chargeability.
If liquidity is a concern, discuss with a financial adviser how to hold funds without selling the home, and do not treat an intermediary's timeline as fact. Re-verify the official terms before each step, since procedures may change. Sequence the decision as read, verify, decide, re-verify, then pay; the sale of the house belongs after residence is granted, not before the application.
A timeline should begin with the current official conditions, readiness of the applicant's funds and identity records, and the processing steps specified by the responsible authorities. It should include a recheck immediately before a payment is made. Hypothetical example: a wildlife illustrator sells securities to fund the payment but schedules the sale before obtaining current program instructions.
The reviewer checks the terms first, records when they were consulted, and only then coordinates the sale, payment evidence, and any separate immigration filing. This order reduces the risk of making an irreversible transfer on an outdated assumption.