  We study type IIA orientifold compactifications with fluxes that give rise to
perturbatively stable, non-supersymmetric AdS$_4$ vacua with D6-brane gauge
sectors. Non-perturbative instabilities can be mediated by D8-branes wrapped on
the six internal dimensions $X_6$, if they reduce to 4d membranes with a charge
$Q$ larger than its tension $T$. The mismatch $Q \neq T$ arises due to i)
curvature corrections and ii) the BIon backreaction of D6-branes wrapping
3-cycles of $X_6$. We give a simple expression for the second effect in
toroidal orientifolds, and find that only pairs of 3-cycles at SU(2) angles
contribute to it. They either contribute towards $Q>T$ or $Q<T$ depending on
the 3-cycles separation, allowing to engineer 4d $\mathcal{N}=0$ vacua in
tension with the Weak Gravity Conjecture for membranes.
