https://github.com/eggert/tz/commit/926b507fa5c3192b1b68fab5910cbd3ba9377c97

From 926b507fa5c3192b1b68fab5910cbd3ba9377c97 Mon Sep 17 00:00:00 2001
From: Paul Eggert <eggert@cs.ucla.edu>
Date: Thu, 5 Sep 2024 14:36:02 -0700
Subject: [PATCH] "Apr", not "April", in IN column

* northamerica (Rule): Use "Apr", not "April", in the IN column.
Both forms are valid, but "Apr" is more consistent.
Problem reported by Howard Hinnant.
--- a/northamerica
+++ b/northamerica
@@ -2631,7 +2631,7 @@ Zone America/Dawson	-9:17:40 -	LMT	1900 Aug 20
 # http://puentelibre.mx/noticia/ciudad_juarez_cambio_horario_noviembre_2022/
 
 # Rule	NAME	FROM	TO	-	IN	ON	AT	SAVE	LETTER/S
-Rule	Mexico	1931	only	-	April	30	0:00	1:00	D
+Rule	Mexico	1931	only	-	Apr	30	0:00	1:00	D
 Rule	Mexico	1931	only	-	Oct	1	0:00	0	S
 Rule	Mexico	1939	only	-	Feb	5	0:00	1:00	D
 Rule	Mexico	1939	only	-	Jun	25	0:00	0	S