  The degeneracy of Landau levels flanking charge neutrality in twisted bilayer
graphene is known to change from eight-fold to four-fold when the twist angle
is reduced to values near the magic angle of $\approx 1.05^\circ$. This
degeneracy lifting has been reproduced in experiments by multiple groups, and
is known to occur even in devices which do not harbor the correlated insulators
and superconductors. We propose $C_3$ symmetry breaking as an explanation of
such robust degeneracy lifting, and support our proposal by numerical results
on the Landau level spectrum in near-magic-angle twisted bilayer graphene.
Motivated by recent experiments, we further consider the effect of $C_2$
symmetry breaking on the Landau levels.
