You've still got a LOT of missing details...
Run the three temps to three disconnects for TEMP power -- only... skid mounted as necessary... this was the norm for Cashe Creek casino a 350,000 square foot slab job. The final Service was at 21 kVolts.
Construction power is typically only a TRIVIAL fraction of the final Service demand.
No-one in my career starts off with a built out Service early in construction.
So, you do have me puzzled.
(200 Amp NEMA3R panels are chicken feed and they may be used/ second hand as temp construction power.)
Followed by a final new Service/ daughter distribution center, with it feed underground at a suitable point in the construction...
Or have a new Poco transformer pad set next to the new Service.
Temp power rules over-ride long term Service requirements. (Oriented towards firemen/ emergency responders needing to kill power with less than six throws from one spot.)
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Stay with aluminum conductors as O/H copper is too heavy.
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An over and under scheme is also possible. I'm forced to guess: is O/H because of a critical access roadway?
( Try horizontal boring -- on a weekend ) Then run the rest of the pipe: cut & cover.)
