Honda doesn’t do build to order like other manufacturers. If you want a certain configuration your dealer doesn’t have, you can have them try to trade with another dealer that has or has been allocated what you want. Since it’s about a month or two from allocation to delivery, that’s roughly how long it could take.
Tony503 has it right - we did our '12 Si that way; took a test drive in a grey one, wanted DBP, took about 2 weeks for the trade to happen. Today's problem will be finding what color you want, the ONLY option is summer tires (all other "options" are dealer installed). Supply/demand will affect wait time and price. My dealer usually has 20+ Civics, this year 2-4 max, currently 0 and no Si yet.
I ordered my 2022 Si on November 13th was told today that it will probably be mid January. My dealership said they have the largest amount of Si pre orders in New England. Luckily I’m told I’m near the top of the list with the majority of their orders coming within the last week after the reviews came out.
I ordered an Si about 10 years ago. After about 3 months, I discovered the truth (described in post #2). Honda doesn't really make a car to order like Chevy or BMW - a dealer tends to get what Honda ships them.
I got my money back once I realized my Si would never arrive.