Monsieur "Kaberi" in 2015 writes well and observes that the events no doubt happened in 1935 (or '36) if Hercule Poirot's reference to his previous letter to the Chinese Laundry in "March 1935" * is anything to go by.
Earlier in the story when Chief Inspector Japp telephones Hercule on the day after the shooting,which, as "predicted" had indeed occurred on the evening of Bonfire Night - November 5th.
Notice if you will, S.I.V.P...that the desk calendar behind Japp has in separate sections "Tuesday" "November" "6" - was this a mistake by the person who oversaw properties, as Bonfire Night, the 5th, itself was on Tuesday in 1935, not Monday,
- or the script editor who should have dropped the year reference* later in the episode?
I haven't checked Miss Christie's original text.
(Edit, having found a relevant page in a review of the book, Chief Inspector Japp states that it happened on Bonfire Night, Tuesday November 5th. It was 1935.
Whoever had the job of setting the calendar in Japp's office made the mistake.
C'est bien, now to look up who that was...ha ha .)
It happened in Hotel Bucharest also. There's an incorrect calendar on a snowy wall, also the thirties.
If my memory is correct it showed October.
Teasers no doubt for all eagle eyed enthusiasts.
I agree with all others thatas usual it's a feast for one's eyes visually.