  In this note, we present a scenario in which the existence of dS vacua is
jeopardized by topological transitions between non-BPS branes and fluxes in
type IIB toroidal compactifications. We focus our study on a six-dimensional
torus compactification modded out by an orientifold three-plane. In particular,
we consider the presence of non-BPS five branes, which allows the construction
of apparent stable dS vacua. Since moduli stabilization requires the presence
of NS-NS fluxes, we also describe the minimal required conditions to avoid the
appearance of Freed-Witten anomalies. Cancellation of these anomalies implies a
topological transformation between non-BPS states and fluxes with the same
discrete K- theory charge. After the transition, we observe that the scalar
potential undergoes major changes, implying that the dS vacua are unstable. We
discuss a scenario in which, even if the discrete K-theory charge is globally
cancelled, the above transitions could still be relevant, allowing the
existence of short-lived dS minima. We briefly comment on how these
implications seem to be in concordance with the Refined de Sitter and
Trans-Planckian Censorship Conjectures.
