We find the spectra at both epochs to contain features due to absorption by ionized material, predominantly due to Ovii and Oviii. We find the opacity for such material to decrease by a factor ~2 in the ~0.7--1.0~keV band between the epochs while the photoionizing flux increases by ~25%. By comparison with detailed photoionization models we show this behaviour is inconsistent with that expected from a single-zone of photoionized gas. A deficit in the data compared to such models, consistent with excess absorption by Oviii, supports the suggestion that the material consists of two or more zones
Significant Fe K-shell emission is also observed during both epochs. We show this emission is dominated by the asymmetric line profile expected from the innermost regions of the accretion flow. We find no evidence that the Fe emission varied in either shape or equivalent width between the two epochs.