It is measured in years rather than months, and depends on processing times, visa availability for the applicable category and country, and the two-year conditional period that follows admission before conditions can be removed.
Plan the household around a multi-year sequence
Hypothetical example: the couple hope to be settled within a year and discover that the sequence has several stages, each with its own duration. The petition is filed and adjudicated; then, depending on where the family is and whether visa numbers are available for the relevant category, either consular processing or adjustment follows; then conditional permanent residence begins and runs for two years; then a further petition removes the conditions, supported by evidence that the capital remained invested and the jobs were created. Each stage has its own current processing estimate published by the responsible agency, and they change.
Meanwhile the project has its own construction and hiring timetable that may not match. Do not sell a house, resign or enrol children on the assumption of a date that no agency has given, and keep the Coaldale arrangements workable for longer than the optimistic estimate.