A Swift Argument for Supernaturalism?

Consider the following deductive argument, consisting of three premises (1-3) and a single conclusion (4).

[1] The explanans for any given explanandum is either natural or supernatural,
[2] Persistence, i.e., the fact that natural things continue to exist, is an explanandum,
[3] There can be no natural explanans for the continued existence of natural things,
[4] Therefore, there must be a supernatural explanans for the persistence of natural things.

This argument is logically valid in the sense that the conclusion (4) follows logically from the three premises. Let us perform a quick evaluation of the plausibility of each of its premises to see whether the argument might be sound as well. Now, premise (1) seems to me indisputable. For even if all explanations would be natural, it would still be true that any explanation is either natural or supernatural. The second premise is perhaps a bit more controversial. Is the continued existence of natural things indeed an explanandum? Is it adequate to ask why natural things continue to exist, or, in other words, is it cogent to ask for that by virtue of which natural things persist in their existence? The third premise seems quite obvious. Surely, if the continued existence of natural things is an explanandum, then its explanans cannot be natural since naturalistic scientific explanations presuppose the continued existence of natural things (in the absense of any natural disintegrating factor). I take it that this argument has force in case premise (2) is sufficiently supported. It has even some force to support theism if we accept Richard Swinburne's dictum that explanations are either scientific or personal. For in that case supernatural explanations, which cannot be scientific, must be personal.