Updating.md

@@ -128,13 +128,14 @@ In addition, you must [create a new public key pair](https://gitlab.torproject.o
 ## Updater URL and Signature Public Certificate
 
 Testing the `nightly` channel is easiest.
+`alpha` and `release` are also feasible, but slightly less automated because our tools take for granted that you are updating from signed builds.
 
 You can change the URL in the [build configuration](https://gitlab.torproject.org/tpo/applications/tor-browser-build/-/blob/main/projects/firefox/config#L38): you just need to set `override_updater_url`.
 This URL will contain the update responses, that are some XML files that the Firefox updater polls with a certain frequency to check if any update is available.
 
 Setting a custom updater URL will also override the update certificate: copy yours to `project/firefox/marsigner.der`.
 
-If you are testing `release` or `alpha` then a more complicated patch will be needed.
+If you are testing `release` or `alpha`, you will have to modify the `build` script to replace the release key instead of the nightly.
 
 ## Sign MAR file
 
@@ -194,6 +195,7 @@ They are located in `tools/update-responses`.
 ### Generate the incrementals
 
 Generating the incrementals has the "side" effect of creating a configuration to create the update responses.
+For nightly you can use use this command:
 
 ```shell
 make torbrowser-incrementals-nightly
@@ -207,6 +209,21 @@ Otherwise, if you really don't want to generate the incrementals, you can simply
 rbm/rbm build release --step update_responses_config --target nightly --target torbrowser
 ```
 
+For `release` and `alpha`, you cannot use the respective `make` targets.
+You will have to use the above command to generate the configuration first, adjust it to use the unsigned build directory:
+
+```yaml
+versions:
+    xx.y.z:
+        releases_dir: .../tor-browser-build/torbrowser/release/unsigned
+```
+
+Then you can optionally generate incrementals manually with:
+
+```shell
+tools/update-responses/gen_incrementals $channel
+```
+
 #### Update the URLs in `config.yml`
 
 `tools/update-responses/config.yml` is a non-versioned file that is generated automatically at the previous stage. \