We present highly-excited charmonium, $D$ and $D$ meson spectra from dynamical lattice QCD calculations with light quarks corresponding to $M$ ∼ 240 MeV and compare these to previous results with $M$ ∼ 400 MeV. Utilising the distillation framework, large bases of carefully constructed interpolating operators and a variational procedure, we extract and reliably identify the continuum spin of an extensive set of excited mesons. These include states with exotic quantum numbers which, along with a number with non-exotic quantum numbers, we identify as having excited gluonic degrees of freedom and interpret as hybrid mesons. Comparing the spectra at the two different $M$ , we find only a mild light-quark mass dependence and no change in the overall pattern of states.