My Russian engineer colleague said "Project schedule is witchcraft."In my experience, for any project involving rail construction in the US, it is prudent to add 3 to 5 years to the original projected date, irrespective of what it involves. And depending on the complexity, doubling the cost before it is all said and done, is usually not outside the realm of possibilities, though there are a few exceptions I can think of. Brightline Florida is not an example of an exception BTW IIRC.