To demonstrate that we have performed the core IP calculation on the same AATT nucleobase tetramer using our SS-FNO-IP-EOM-CCSD* implementation augmented with the projector-based quantum embedding (PBQE) method of Waldrop et. al. The details of the benchmarking of the accuracy of PBQE-SS-FNO-EOMIP-CCSD* has been provided in the supporting information. The cc-pCVTZ basis set has been used for the calculation on AATT, which leads to 2045 molecular orbital. One of the thymine molecules is taken as active and is embedded in the Hartree-Fock density of the entire AATT molecule. With the use of the PBQE-SS-FNO-EOMIP-CCSD* method, the number of correlated electrons is reduced to 66, and the size of the virtual space is reduced from 1909 to 249 only. The SS-FNO-IP-EOM-CCSD* binding energy corresponding to the lowest core orbital in the AATT complex is 537.24 eV, which shows excellent agreement with the corresponding calculation on the full system.