Hi Colin,

There is only one internal format that uses the GEDCOM form 5 SEP 2020 or 5 JUN 2020

But there are many display formats and they can be customised independently for Diagrams, Narrative Reports, Queries, Records Window Columns, etc.

So it depends where you want the LONG format displayed.

The format codes are explained in FH Help > Family Historian Help > Using Family Historian > General Topics > Date Formats

In the Property Box, FH uses ABBREV2 format and that cannot be customised.

In Diagrams see Diagram > Options > Text > Edit > Date Format where you can set Long format.

Most Reports just use ABBREV2 format, but Narrative Reports are governed by the Sentence Templates where such as {date:LONG} works.

In Queries and elsewhere in Expressions you can use such as %INDI.BIRT.DATE:LONG% or any other format qualifier.

Regards, Mike Tate