Zip Code vs Zip Code Survey in Analytics

I recently learned about the T_DEFAULTS setting "General Public Zip Question ID" that allows Analytics to pull in the Survey Question from "0" General Public orders as a zip code for overall Analytics evaluation - and this has been awesome for us.

We have a new quandary that I'm not sure the answer.

In a somewhat archaic way, we have an event where we intend to collect first name, last name, email, and zip code on paper for guests who wait in line for an Adult Night. Then, when they make their Walk-Up purchase, the cashier will write down the Order Number on the piece of paper (this is all about keeping the line moving on this busy night, rather than real-time data entry - I know, this is its own topic :). Later, we intend to have staff look up the order and attach it to a purchaser knowing that most will be new constituent records that we will create.

So, with that set-up, my question is - at the time of purchase, the Cashier will have input a Zip Code into the survey field. When we later go back and add a constituent with a known Zip Code in the Zip Code field...what happens in Analytics? There will be two zip codes (that hopefully match) From an Analytics standpoint, which Zip Code is the recorded Zip Code? Will it pull both and skew data? Does anyone know the logic behind dueling Zip Codes?

Hopefully this makes sense. And, hopefully a Tessitura Staff member may be read this, too!

Thanks in advance,

-Mark