Yes, in that it could be open-ended in any "direction" independent of the delusion. However, that might require contrived initial conditions or cognitive architecture. You might also find the delusion becoming neutralized for all practical purposes, e.g. the delusional proposition is held to be true in "real reality" but all actual actions and decisions pertain to some "lesser reality", which turns out to be empirical reality.
ETA: Harder question: are there thinking systems which can know that they aren't bounded in such a way?
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