Maybe you haven't noticed a lot have changed in Crystal Palace. It all started from when Oliver Glasner, who took the reins in February 2024 as the new head coach (manager). Since then there have been an improvement in the team with enough evidence to back up the claim. However, is contract will be expiring in the 2025-2026 season, and after that he may choose to sign a long term contract or leave the club. In the meantime, they are confident against Chelsea on that match day and I believe so too.
Yes, after Oliver took over Crystal Palace, I also noticed that they made quite rapid progress. This is evident in the FA Cup, where they defeated a major team like Manchester City. So, considering this, we can all agree that Oliver has had a significant impact on Crystal Palace's progress.
Regarding their first match of the season, which is scheduled against Chelsea, this will certainly not be an easy match for Crystal Palace, as Chelsea is currently in excellent form. Evidence of this is their victory in the recently concluded World Cup. So, with this in mind, I think Crystal Palace must prepare their team to perform even better against Chelsea.
Regarding Oliver's contract, I believe that if he can make even more significant progress at Crystal Palace, he will likely be offered a contract extension by Crystal Palace. However, if a manager can transform a mid-table team into a formidable one, there are usually many teams interested. So, if Oliver receives an offer from a major team after his contract expires, I don't think it's impossible for him to choose to coach there. So, I think it depends on Oliver's decision next season.