First of all, I would like to thank everyone working on this project. It eases our changelog generation a lot!

After upgrading our dependencies I have spotted some changed behavior. To illustrate this, I have created a fresh Python 3.9.4 project with just minimal code and towncrier==21.3.0.

When I configure towncrier like this:

[tool.towncrier]
title_format = "{version} ({project_date})"

Then the output of towncrier build --version=0.1 --draft is

0.1 (2021-04-27)
=================

Features
--------

- This is only a test. (#1)

as expected. However, the content of NEWS.rst after towncrier build --version=0.1 is

0.1 (2021-04-27)0.1 (2021-04-27)
================

Features
--------

- This is only a test. (#1)

where we can see that the title is duplicated.