The aforementioned list of 2023 public holidays in the Western Australia contains the footnote "Monday 26 December 2022 is a Boxing Day public holiday and also an additional Christmas Day public holiday at the same time".
Then, later during the year, that initial listing of public holidays is completed with the formal announcement of the date of the Queen's Birthday public holiday (2020-09-23, 2019-12-04 and 2018-04-22).
However, in a marked departure with tradition, the list of 2023 public holidays in the State of Western Australia, lists a definite date for the Queen's Birthday public holiday, a date which in fact represents an exception with respect to the rule usually used to calculate the the Queen's Birthday public holiday in Western Australia.
Mention is also made of the regionally varied dates on which the Queen's Birthday public holiday can be observed ("Some regional areas in WA hold the Queen's Birthday public holiday on a different date - the 2021 dates have not been proclaimed").
Links and References
Below are links to the news stories referred to in the above "Western Australia 2023 Public Holidays Released" news story, as well as links to subsequents news stories which refer to the present news story.