Every year, no later than the 25th of January, DFAS-CL will send you an Internal Revenue Service (IRS) Form 1099-R which will show all the taxable retired pay paid and the amount of tax withheld ...

This requires that the address on file with DFAS be currently. ... This is done using IRS form 4868. This automatic extension will push your tax return due date to 15 October 2014.