We investigate the exact-WKB analysis for quantum mechanics in a periodic
potential, with $N $ minima on $S^{1}$. We describe the Stokes graphs of a
general potential problem as a network of Airy-type or degenerate Weber-type
building blocks, and provide a dictionary between the two. The two formulations
are equivalent, but with their own pros and cons. Exact-WKB produces the
quantization condition consistent with the known conjectures and mixed anomaly.
The quantization condition for the case of $N$-minima on the circle factorizes
over the Hilbert sub-spaces labeled by discrete theta angle (or Bloch momenta),
and is consistent with 't Hooft anomaly for even $N$ and global inconsistency
for odd $N$. By using Delabaere-Dillinger-Pham formula, we prove that the
resurgent structure is closed in these Hilbert subspaces, built on discrete
theta vacua, and by a transformation, this implies that fixed topological
sectors (columns of resurgence triangle) are also closed under resurgence.