If you are referring to the $10,000 exclusion for veterans who are under the age of 55 (it used to be $5,000), please note that the current (2018) Maryland instructions still list the $5,000 exclusion, which is what TurboTax uses (see code u on page 8 at the state website).
Note that the Maryland's Comptroller Office's website still reports $5,000.
I would suggest that the Veterans Affairs website that you refer to may be referring to an increase that takes effect for tax year 2019.
If you have any further information that this applies to tax year 2018, please let us know in the comments.
