๐ค Why is there 17 July on the ๐ โCalendarโ emoji?
There are several emoji where the design details are not random or carry a hidden meaning. These include ๐ "Open Book", for example, where the Apple version displays real text, and the emoji for ๐ง Deaf people showing a word from European Sign Language.
"What about the July 17 ๐
"Calendar" emoji?", often wonder frequent users and emoji โค๏ธ Lovers.
What are the origins of this date?
Later, in 2014, emoji reference website creator Jeremy Burge had the idea of organising an annual ๐ Celebration dedicated to emojis. And since the emoji calendar on the iPhone displayed July 17, Jeremy thought it was logical to celebrate ๐ ๐ World Emoji Day on that very day.
The idea of celebrating proved to be successful. Consequently, the major platforms, starting from 2016, have altered the numbers on their emoji calendars to July 17 in order to avoid user confusion.

Note: on Apple, Samsung, Google and the Mozilla browser, the 17 July is also displayed by the ๐ "Tear-Off Calendar" emoji.
What about other emoji-dates?
Calendars on other platforms either look generic, like Microsoft's, or even display random numbers. For example, 12. Although the latter has been suggested as representing the number of months in a year, no clear proof of this theory has been found.