To request an extension for the 2024 tax return you will need to wait until the IRS has the 2024 Form 4868 finalized which is usually in either January or February. You would need to complete, download, print and mail the Form 4868. Access the form in 2025 from this IRS website - https://www.irs.gov/forms-pubs/about-form-4868
TurboTax will normally have the Form 4868 available to be e-filed in mid-March so if you are still traveling you would be able to e-file the extension request from the TurboTax Easy Extension website.
Note - The extension request gives you an additional 6 months to file the federal tax return not an extension to pay taxes owed. If you have taxes owed on the 2024 return those taxes have to be paid on or before April 15, 2025 to avoid a failure to pay penalty.
