Sounds like he has it set up so he can find the best wall, and continue to keep things competitive to keep the costs down.
I’d like to see it done by the time he has to run again.
I think there could be a lot of it built in the next 3.5 years. However, I don’t anticipate that it would all be done. Main big runs, sure, but tricky areas could get skipped while they figure out what to do with a tributary stream etc.
When big runs of miles of an impressive wall is ribbon cut, it makes for great television. Big beautiful or Big ugly depending on the network and the presentation. Theater!