Thanks so much, ls_rbls. Since I'm new to Acrobat DC, can you tell me where I find the window shown in your image?
And yes, I have quite a few date fields in the form. Thanks for the heads up about how they will submit.
You're welcome.
I assumed that you were using a button with a "submit form" menu action.
You won't be able to edit this PDF in Adobe Reader DC though.
To do so, you need the full desktop version of Adobe Acrobat Pro DC (paid subscription).
If you do have Acrobat Pro DC, use the "Prepare Form" tool (some people refer to it as "edit mode").
When you open this tool you'll be able to edit the formfield objects in the PDF document.
For example, if you do have button field object, right-click on it, and select "Properties" from the context menu.
This will open the field properties dialogue window as shown in the screenshot.
Then click on the "Actions" tab. See below that the section labeled "Select Action".
From the dropdown menu next to that select "Execute a Menu Item"; scroll down on that list and select "Submit a form".
The "Submit Form Selections" dialogue box will open next, which is shown in my screenshot.
This is where you can select all fields or "Only these.." fields.