When I type the date in the column as 17/08/19 it’s always appeared that way but now in the updated version it will appear as 17/08/2019. How can I get it back to how it was?
Did you change your locale or some related settings like the default language for documents?
If I do as you described with LibO V6.3.0.2RC under English (UK) locale and Default - English (UK) as the language entry in the ‘Numbers’ Tab of the cell formatting dialogue, I get what you expected.
By the way: That’s very bad. Always format your dates (you have a dedicated column as it seems) as decribed by the code YYYY-MM-DD. This SHOULD be the default format for all locales IMO .
See this cartoon.
I personall have additionally set my Date acceptance patterns: to D.M.. to ease entry a bit regarding old habits. You may use in this place D/M/ e.g.
You may also consider to edit the subject. The stars are ambiguous and the second “19” at the end is misleading.
If you use an example you will surely choose one that disambiguates against the US style dates (day number > 12).
You have to check Tools>Options, LibreOffice General. The setting Yaer (Two Digits) defines the threshold for the century.
If your 2-digit year is below the threshold, then you’re in the XXth century (19…). Above the threshold, you’re in the current century (20…).
If you want to enter 2-digit XXth-century years, set the threshold to any suitable value for you. Note however this will not correct already entered dates, the feature is active only when typing new dates.
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EDIT
I may not have understood your question. I based my answer on the title. As @Lupp noted, the “19 19” is misleading. Please correct the ambiguity as my answer may not address your question.
Format Cells… / Numbrers
Category: Date
Format code: DD/MM/YY
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