Not reliably, because processing times and the status conferred are matters for the official program and can change. Contracts should be conditional on the builder holding a status that permits the work, and any state licence, before a start date is promised.
A client's calendar is not a processing time
The sequencing failure here is familiar from every category: a start date promised to a third party before the immigration decision exists. With a new program the uncertainty is greater, because processing expectations have less history behind them. The builder should therefore reverse the order.
First verify the program's terms and note what it says about timing, if anything. Second, apply through the official channel and keep the acknowledgement. Third, pursue state licensing in parallel, since examination and bonding timelines are independent of immigration.
Fourth, offer clients a contract conditioned on both the status and the licence, with a start date to be fixed by notice once both exist. Meanwhile he may visit as a business visitor to walk lots and discuss plans, but may not supervise work or hire crews. If the clients cannot wait, they should engage a licensed local contractor for the first season, and the builder can plan to take over later projects once his position is settled.