when i start s a ecommerce their is no option to fixed shiping i thnk to add field in default cod
with Akamai mpulse script .
simply you have to make a extension on ecommerce platform for fixed time shiping for used
i thinks its for abantecart and opencart
i have some file you have to add some changes there i thinks .
fixed shiping catch there time on the day means a order given in 20 september 2 pm then clock automatic set time after 5 6 hours . for example fern n patel [login to view URL] do in their site
all is this you have to make an extension for fixed time shiping