Issue Summary

When manually entering the date without the year into the date picker field, the value will follow the month/day format instead of the format configured in the java date picker setting.

Steps to Reproduce

To confirm you are affected by this bug:

• Set/verify jira.data.picker.java.format and jira.date.picker.javascript.format in Jira Advanced Configuration settings to follow a format where the date goes before the month in case this was updated. The default setting already follows a format where the day goes before the month.
• Set/verify date and time configurations in the Look and feel settings to follow a format where the date goes before the month. The default setting already follows a format where the day goes before the month.

Once confirmed that your date settings are configured for Day/Month format, carry out these steps to reproduce the behaviour:

1. Create a new date picker field and add to the create issue screen
2. Create issue.
3. Manually enter the date using the DD/MM format (excluding the year). For example: 01/07
4. Select the calendar date picker
5. Observe that this will default to January 7th, not July 1st.

Expected Results

Date format should respect the date settings configured under General configuration:

jira.date.picker.java.format
jira.date.picker.javascript.format
jira.date.time.picker.java.format
jira.date.time.picker.javascript.format

Actual Results

Date format is defaulted to MM/DD

Workaround

Manually enter the date in three digit format, e.g. Jul for this to work as DD/MM.

Set the date using the calendar date picker.

Include the year when manually entering the date. For example 01/07/2025