The Secret of the Flame Tree - S6-E2
Character mistake: Florence says that the verses Esther was researching were 'halfway through' the book, but Humphrey opens a page in the last 1/4 of the book. (00:29:40)
The Secret of the Flame Tree - S6-E2
Character mistake: Florence says that the verses Esther was researching were 'halfway through' the book, but Humphrey opens a page in the last 1/4 of the book. (00:29:40)

Continuity mistake: When Aunt Mary is writing on the whiteboard at the hospital, the word "killed" changes style between shots. (00:31:40)
DI Jack Mooney: Strictly speaking, paradise is a state of mind. You know that, right? I mean, the dung beetle - very different idea of paradise, doesn't he? (00:48:25)
Trivia: A bit of the episode has been cut for the streaming releases; at the end of the scene with Humphrey taking Martha's luggage, he would make a date with her for the next day, to cook dinner for her at 8. This has been eliminated probably because it created timing issues with 8 PM being too well lit (in contrast with the supposed timing of the murder) and the ending takes place at Catherine's for a cute drinking scene anyway. (00:22:50)
Question: Why did the cord on the wall phone in the police station change from straight in the early episodes to coiled later?
Answer: There's probably no particular reason. Sets and props on long-running TV shows often change as needed and for various reasons throughout a series run.
raywest ★
As long as such changes aren't an obvious continuity mistake (e.g. changing multiple times during a day), one can just assume the change happened in-universe as well. Things do get broken or updated occasionally. It adds a bit of realism, in my opinion.