Update documentation

hypothesis-python/docs/settings.rst

@@ -251,15 +251,14 @@ by your conftest you can load one with the command line option ``--hypothesis-pr
 
 
 Hypothesis comes with two built-in profiles, ``ci`` and ``default``.
-``ci`` is set up to have good defaults for running in a CI environment, so emphasizes determinism, while the 
+``ci`` is set up to have good defaults for running in a CI environment, so emphasizes determinism, while the
 ``default`` settings are picked to be more likely to find bugs and to have a good workflow when used for local development.
 
-Hypothesis will automatically detect certain common CI environments and use the CI profile automatically
+Hypothesis will automatically detect certain common CI environments and use the ci profile automatically
 when running in them.
 In particular, if you wish to use the ``ci`` profile, setting the ``CI`` environment variable will do this.
 
-If you want to customise your CI behaviour, registering a new version of the ``ci`` profile will automatically be picked up in CI. For example, if you wanted to run more examples in CI, you might configure it as follows:
-
+This will still be the case if you register your own ci profile. For example, if you wanted to run more examples in CI, you might configure it as follows:
 
 .. code-block:: python
 

hypothesis-python/src/hypothesis/_settings.py

@@ -317,6 +317,10 @@ def register_profile(
         :class:`~hypothesis.settings`: optional ``parent`` settings, and
         keyword arguments for each setting that will be set differently to
         parent (or settings.default, if parent is None).
+
+        If you register a profile that has already been defined and that profile
+        is the currently loaded profile, the new changes will take effect immediately,
+        and do not require reloading the profile.
         """
         check_type(str, name, "name")
         settings._profiles[name] = settings(parent=parent, **kwargs)