| ubi-cons(apebs, vols, wlar, q, bflipset, vtblpnum, sqnum), bflipset0 = bflipset ⊦ ⟪ubi_get_pebs_for_wl#(wlar; n, m, bflipset; boolvar)⟫ ( ubi-cons(apebs, vols, wlar, q, bflipset, vtblpnum, sqnum) ∧ ( boolvar → n < # wlar ∧ wlar[n].status = free ∧ m < # wlar ∧ wlar[m].status = used ∧ (bflipset0 = ∅ → wlar[n].ec ≥ wlar[m].ec + WL_THRESHOLD))) |