From my perspective, it is problematic to assign the gods the activity of maintaining their "incorruptibility" through their actions. That implies to me that if they, for some reason, fail to maintain themselves that would be a source of anxiety for the gods. They would have to remain vigilant every minute, maintaining, checking, working to keep balance in their atoms, or some such thing. That seems incompatible with Epicurus's whole definition of divinity. To me this excerpt from Diogenes Laertius implies that not only do the gods not experience an increase in pleasure but they do not experience any decrease as well. If their "incorruptibility" aspect dips a little and they have to maintain it, that implies a decrease in pleasure as well.
Quote from Diogenes Laertius 10.121Happiness must be understood in two senses; the highest happiness, such as is that of God, which admits of no increase; and another kind, which admits of the addition or abstraction of pleasures. (Yonge)
[121] Τὴν εὐδαιμονίαν διχῆ νοεῖσθαι, τήν τε ἀκροτάτην, οἵα ἐστὶ περὶ τὸν θεόν, ἐπίτασιν οὐκ ἔχουσαν: καὶ τὴν <κατὰ τὴν> προσθήκην καὶ ἀφαίρεσιν ἡδονῶν.
VS33 also says "The body cries out to not be hungry, not be thirsty, not be cold. Anyone who has these things, and who is confident of continuing to have them, can rival the gods for happiness." To me, a god would not have a body that cries out to not be incorruptible. I suppose someone could counter that the gods are "confident of continuing" to be incorruptible.
The paper by Geeta Raghunanan provides an interesting solution to the incorruptible seen as eternal issue:
QuoteI contend that they may be imperishable; that is, the Epicurean gods may be destined to dissolution and yet be imperishable in the sense that they are impervious to decay or corruption, particularly, what might be termed moral decay or moral corruption. ... But I emphasize “moral corruption” or “moral decay” also to incorporate Epicurean descriptions of the gods that seem to suggest that imperishability might in fact have meant to the Epicureans imperviousness to moral corruption. ... it is possible
to maintain that given an Epicurean physical theory and the doctrine that all compounds will dissolve, the Epicurean gods, as compounds, are yet still imperishable in the sense that they are morally incorruptible.
This appeals to me - if I were to accept the idea that the Epicureans thought of the gods as living beings. One of my main objections to "god as living being" vs "god as conceptual metaphor" is that I can't reconcile Epicurus's foresight and critical thinking with believing in a physical god... However, Raghunanan narrowing of αφθαρτον to "incorruptible" ie "not able to be corrupted, from a moral/ethical perspective" - with the understanding that the gods will eventually physically decay due to their being material compound beings is enticing. And, if the gods do die, it would be nothing to them as they have lived in the midst of unceasing pleasure.
Things to think about for me at least.