Actually they are not yet fully stable, because they still need time to be able to restore something that was lost after the problems they faced. At least now it's much better than last season, and now they're starting to come back with something new. After all they are one of the big teams that are expected to give their best performance.
Yes, and I believe that Chelsea are still able to fix something that was lost by targeting some new players so that their performance can improve next season even though at the moment Chelsea doesn't seem to be getting too many new players through the transfer market. But in essence Chelsea are also trying to make the club's performance better than before.