Note that the law [SDCL 4-7-9] says it should be presented “after the first Monday of December immediately preceding the session for consideration either with or without amendments and modifications by the Legislature.” I’m kind of taking it that the law’s intent is that the legislature has the power to modify it after presentation - and there isn’t any allowance for the executive branch to have a do over. [Pat Powers, "So, If It Isn't on Time, Is It a 'Legal Budget'?" Dakota War College, 2009.01.14].
I would love to see the Legislature fight for its proper power, dig into the original budget proposed in December, and make all the necessary changes themselves. Alas, our legislators—even the Democrats—don't have quite the fight in their souls that they should have against an executive branch that continues to over-extend its authority.