If there is a second mortgage on the property, the holder must agree to subordinate the lien, so that new VA loan becomes the first mortgage (valoancaptain.com)
If you were to sell your home then the first mortgage holder would get paid first from the home sale while the second mortgage holder would get paid after. (mortgagebrokerstore.com)
In such a case, the second mortgage holder may have to wait until the first mortgage holder is paid off before they can be paid. (mortgagebrokerstore.com)