  The FCC-ee impedance model is being constantly updated closely following the
vacuum chamber design and parameters evolution. In particular, at present, a
thicker NEG coating of 150 nm (instead of previous 100 nm) has been suggested
by the vacuum experts, and a more realistic impedance model of the bellows has
been investigated. Moreover, also the transverse impedance has been updated by
considering the same sources as for the longitudinal case. Therefore, the
FCC-ee impedance database is getting more complete and the impedance model is
being refined. In this paper we describe the presently available machine
coupling impedance in both longitudinal and transverse planes, and study the
impedance-driven single bunch instabilities (with and without beam-beam
interaction) for the new FCC-ee parameter set with 4 interaction points (IPs).
The results are compared with the previously obtained ones and a further
possible mitigation of the beam-beam head-tail instability (X-Z instability) is
proposed.
