I think Chelsea is still not at their peak, but if we look at their performance last season and what they have gone through now, so it can be assumed that they have experienced quite a good improvement. If only they could play consistently and not only play well when competing against big teams, I think Chelsea will have a chance to break into the top 4. Chelsea will face Newcastle in the next match, this will be quite a tough battle for them because they will be playing as guests but they still have a chance, considering that Chelsea often plays well against big teams.
I agree that Chelsea isn't in their best form yet. If they are in the best form, they won't be in the 10th place now, they should be in the top 5 of EPL standings. We must remember that Chelsea was one of the top teams in EPL, they were joining the race for the title. But now Chelsea is no longer a top team, they seems like an average team only. So, it is a big task for Pochettino to rebuild Chelsea squad to be as strong as again in the previous seasons.
However, it is true that their current performance showed a good progress. They could win against Tottenham and steal points against Man City, it is a really positive progress for Chelsea currently. But it won't be easy to maintain the good performance, I expect Pochettino knows how to deal with any obstacle in Chelsea.
Well, for the next match, I think Chelsea has a chance to beat Newcastle although it won't be easy since the match will be held in Newcastle home.