Confusion on the sign of CI coefficient in singlet state CI wavefunction in PySCF

Hello everyone,

I am facing an issue regarding the sign of CI coefficients of a CASSCF wavefunction computed by PySCF. I was running an SA-CASSCF calculation on O2 molecule with an active space of 4 orbitals and 2 electrons taking 1 triplet and 4 quartets for state-averaging. I got the following configuration for each state in the output,

** Largest CI components **** Largest CI components **
  [alpha occ-orbitals] [beta occ-orbitals]  state 0   CI coefficient
  [0 1]                []                             -0.999961442607
  [alpha occ-orbitals] [beta occ-orbitals]  state 1   CI coefficient
  [0]                  [0]                            -0.670677953622
  [1]                  [1]                             0.737204894786
  [alpha occ-orbitals] [beta occ-orbitals]  state 2   CI coefficient
  [0]                  [1]                             0.704828210369
  [1]                  [0]                             0.704828187689
  [alpha occ-orbitals] [beta occ-orbitals]  state 3   CI coefficient
  [0]                  [0]                             0.738528199450
  [1]                  [1]                             0.671826029081
  [alpha occ-orbitals] [beta occ-orbitals]  state 4   CI coefficient
  [1]                  [2]                            -0.705973331057
  [2]                  [1]                            -0.705973124345

The corresponding S^2 values are,

state 0  E = -149.65917380939 S^2 = 2.0000000
state 1  E = -149.612964346535 S^2 = 0.0000000
state 2  E = -149.612300584601 S^2 = 0.0000000
state 3  E = -149.568898604759 S^2 = 0.0000000
state 4  E = -149.177928151749 S^2 = 0.0000000

Looking at the alpha and beta occupations, state 2 appears to be an open-shell singlet state which is an approximate linear combination of |αβ00⟩ and |βα00⟩. To the best of my understanding the open-shell singlet state can be represented as 1/(√2)(|αβ00⟩−|βα00⟩). So shouldn't the CI coefficients be 0.704828210369 and -0.704828210369 instead of both being positive?