Why do some previews not correspond with the next episode?

[ShuaiJanaiDesu 1]

So recently I've been rewatching some old episodes and noticed that the preview at the end of the show doesn't match with the episode order/number.

 

For example, I was watching episodes 138-139 (The Final Screening Murder Case) and the preview & next conan's hint at the end of 139 was NOT for 140. Then I watched episode 140(SOS! Messages from Ayumi) and the preview & next conan's hint was for episode 138. So they seem out of order.

 

One hypothesis might be because I'm watching them online on streaming sites, so the videos might have been edited (but I don't think this is highly likely).

Another guess might be that the animation studios may have made the mistake. (I also think this is unlikely)

Another might be that the episode number is wrong. (I would have to say this is most likely out of the three)

 

So I was wondering if anyone knew why the previews aren't corresponding with the episode numbers?

 

EDIT: I should have done more research. I looked at the Japanese wikipedia page(名探偵コナンのエピソード一覧) And there I found out that episode 140 was put into an earlier DVD than episode 138-139. So in the DVD, episode 140 comes right before episode 138-139.

Seems like I can't delete posts(i think?) so I'll just leave this as is. Sorry for the commotion

[Niels Nable 0]

I'm currently watching old episodes of Detective Conan, and I noticed this as well.?I'm surprised that another person in this world made the same observation. Haha.