doc: added instructions for manual site release to README.md

Author: geoffroy-noel-ddh

README.md

@@ -101,16 +101,27 @@ how to add static pages to the site via markdown files.
 ## Editorial and release workflow
 
 Changes to the content or code should normally happen on the `develop` branch. 
-Any commit on that branch will automatically trigger a release to the **[staging/preview site](https://kingsdigitallab.github.io/corpus-building/)**.
+Any commit on that branch will automatically trigger a release
+to the **[staging/preview site](https://kingsdigitallab.github.io/corpus-building/)**.
 
 Once the changes accumulated on the staging site are ready for public release
-they can be merged into the `main` branch by a developer or with [a new Pull Request](https://github.com/kingsdigitallab/corpus-building/compare/main...develop).
-Any update of that branch will automatically trigger a release to the Oxford **[public/live/production site](https://sicily.classics.ox.ac.uk/)** via SSH.
+they can be merged dierectly into the `main` branch by a developer. 
+Alternatively non-developers can create 
+[a new Pull Request](https://github.com/kingsdigitallab/corpus-building/compare/main...develop)
+to be reviewed and merged by someone else.
 
-In both cases [the automated release process](https://github.com/kingsdigitallab/corpus-building/blob/main/.github/workflows/frontend.yml) from a modified branch first does the following:
+Any update of the `main` branch will automatically trigger a release 
+via SSH to the **[public/live/production site](https://sicily.classics.ox.ac.uk/)** 
+hosted on Oxford server.
+
+### Automated release process
+
+In both cases 
+[the automated release process](https://github.com/kingsdigitallab/corpus-building/blob/main/.github/workflows/frontend.yml) 
+from a modified branch first does the following:
 1. fetches the latest version of the TEI corpus from https://github.com/ISicily/ISicily
 2. run the ETL process from that corpus to rebuild the site metadata and indices
-3. run some automated tests and stops the release if they fail
+3. run some automated tests and stops the release if any fails
 4. commit the updated metadata and indices to the branch
 
 The release process may take up to 30 minutes to complete. 
@@ -121,10 +132,38 @@ and the actual refresh of the content on the target site.
 Also note that [hard-refresh in your browser](https://www.wikihow.com/Force-Refresh-in-Your-Internet-Browser) 
 may be needed to flush old, cached content.
 
-Small **hot fixes** to the code or content of the live site can be done 
+### Hot fixes
+
+Small **[hot fixes](https://en.wikipedia.org/wiki/Hotfix)** 
+to the code or content of the live site can be done 
 with a Pull Request directly on the `main` branch. 
 In that situation extra care should be taken when verifying the changes.
 
+### Changes to the corpus
+
+Although the automated release process pulls [the latest version 
+of the TEI corpus from the `main` branch of the ISicily repository](https://github.com/ISicily/ISicily/tree/master/inscriptions),
+only changes in the code of this repository will trigger the process.
+
+If you only want to update the metadata about the TEI corpus on a site 
+(staging or production) then you can manually trigger the release process
+by following those steps:
+1. go to the [Build and deploy workflow](https://github.com/kingsdigitallab/corpus-building/actions/workflows/frontend.yml) on the Corpus Building repository;
+2. click the "Run workflow" dropdown on the right,, just above the table;
+3. select the relevant branch (`main` for live site, `develop` for staging site);
+4. confirm by clicking the "Run workflow" button
+
+You should be redirected to a new page for that release job 
+where you can see its running status in real time. 
+You'll notice a "Cancel workflow" button in the top right corner
+to interrupt the job. You can't resume a cancelled job; 
+instead you would run a new one.
+
+You can also see all the current and past jobs on the Build and deploy page.
+The color of the icon in fron of each row indicates the status of the job:
+animated orange is curently running; blue tick was successful; 
+red cross failed; and greyed was cancelled.
+
 ## How to cite
 
 ```bibtex