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.
Chelsea is called an unstable team we can see it from the start of the season well, in the last 2 matches they played well but we can't guarantee that they can do it again in the next match somehow, when we hope they win, the opposite happens lol. I can't guess about the upcoming Chelsea match because both teams are at the same level Chelsea has the advantage of being a on fire team and Newcastle of course as the home team also has an advantage so I think the chances are 50:50.