Should I submit my returns if I live abroad but haven't reached 330 days yet or request an extension?

[KarenJ]

You need to request an extension until you qualify for the foreign earned income exclusion.

If you have a foreign address, the IRS extension, Form 4868, does not have fields for a foreign address.  Therefore if you file your extension in TurboTax, it will not accept a foreign address. If this applies to you, you will need to file a paper extension.

https://www.irs.gov/pub/irs-pdf/f4868.pdf

If you are living and working abroad on April 15th, the IRS allows an automatic 2 month extension until June 15th.  However, if you have a balance due, interest will accrue until June 15th.

To use this automatic 2-month extension, you must attach a statement to your return explaining that you were living abroad on April 15th.