Is there a way to populate a new form with an existing for data and assign it to a person with additional entry fields?

Is there a way to populate a new form with an existing for data and assign it to a person with additional entry fields?
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This is possible to allow another person to update submissions. You may take a look at the next guide to get an idea about a possible configuration:

A General Approach on Building an Approval Process Workflow

Or do you need to receive separate form submissions? If so, do you want to populate the same form, or a different form?

I created a form whereby potential borrowers submit their information with 2 references.

Note: how to save each form uniquely and save the data on the phone until there is internet connection to be able to transmit the form.

Now, I want a created a new form by populating information from that borrower with new field entry for the credit officer if certain conditions are met such as:

1. Borrower- Client complete application form online at our website or thru our mobile phone application. Then the application is assigned to the loan officer closest to the client.
2. Credit Officer call to verify that the borrower has a business whether formal or informal: if no, the process must stop 🛑 because the credit officer will not be able to evaluate the repayment ability of the borrower using the cashflow method.
3. If yes that the borrower has a formal or informal business, then the credit officer can move to step 2 of the loan application process.

B. Step 2: LOAN APPRAISAL

1. Call up the 2 references submitted by the borrower to confirm they know the borrower. If the 2 references confirmed knowing the borrower in a positive manner then credit officer move to #2. However, if Crédit officer is only able to verify only 1 reference, then the Credit Officer must stop 🛑 processing that particular loan application and notify the borrower.
2. Credit Officer call the borrower to schedule a site visit to analyze his or her business. If the applicant does not show up for the appointment then it can be rescheduled one more time only. 
3. FIRST VISIT TO BUSINESS LOCATION - Credit Officer completes Loan Appraisal form and Cashflow form while conducting the site visit. Please capture the GPS coordinates of the borrower business with date and time stamps from the mobile phone since some businesses do not have formal and physical addresses.
4. If the indicator is negative, then the credit officer must stop 🛑 the loan process and indicate to the borrower that based on the information submitted to perform the cash flow analysis, he or she will not be able to repay the loan. Then be polite and thank them for applying.
5. FIRST HOME VISIT - If the indicator is positive then the loan officer must schedule a visit at the residential home of the applicant. That step must be done without exception. If the applicant does not agree to a visit to his residential address, then the loan application process must stop 🛑. Just be polite and thanks the applicant for his or her time.
6. At conclusion of first home visit, credit officer must capture in our mobile app or form the GPS coordinates of the borrower residential address with date and time stamps from the mobile phone
7. 2ND SURPRISE VISIT - Credit Officer must complete a 2nd but surprise visit to the borrower if the loan amount is 100,000 gourdes and above. If there are any signs of fraudulent activities, then the credit officer must stop 🛑 the process.
8. Final analysis and loan structuring
9. Final review by USA Office 

You can set the offline mode using the JotForm Mobile Form App.

Guide:https://www.jotform.com/blog/how-to-get-work-done-on-the-go-with-offline-forms/

You may populate the fields from an excel file using the Spreadsheet to form widget.
https://www.jotform.com/help/442-How-to-Use-the-Spreadsheet-to-Form-Widget

You can also send the notification emails depending on condition.

Guide:https://www.jotform.com/help/167-How-to-Send-Email-Based-on-User-s-Answer

This can be used to send the notification depending on address or your condition.

Hope this information helps.

For the offline option to save the form data when they have little or no WiFi or internet access, does it work for my plan type with JotForm?

Yes, it does works for every plan. And when you will get online, the data will sync and you can see the same data when you will log in from browser.

Feel free to reach us in case you have any further questions.