Frankly, if the goal of the administrations was to be helpful to Russia's offensive, then halting shipments while muddying the waters with inconsistent messaging would be an excellent way to accomplish that.

Stop the shipments, but lie about it and say that you will ship more in the future. Then just never actually do that. This keeps them hoping for shipments that will never actually arrive.

edit: Another possibility here is that the Def Sec Hegseth does not want to help Ukraine, but Trump himself does not actually care one way or another, and thus could be convinced to overrule his Def Sec.

Tough to say.