  In the framework where the strong coupling is dynamical, the QCD sector may
confine at a much higher temperature than it would in the Standard Model, and
the temperature-dependent mass of the QCD axion evolves in a non-trivial way.
We find that, depending on the evolution of $\Lambda_{\mathrm{QCD}}$, the axion
field may undergo multiple distinct phases of damping and oscillation leading
generically to a suppression of its relic abundance. Such a suppression could
therefore open up a wide range of parameter space, resurrecting in particular
axion dark-matter models with a large Peccei-Quinn scale $f_a\gg
10^{12}~\mathrm{GeV}$, i.e., with a lighter mass than the standard QCD axion.

High Energy Physics - Phenomenology