docs: fixes and improvements (#839)

Author: csviri

docs/documentation/faq.md

@@ -5,10 +5,36 @@ layout: docs
 permalink: /docs/faq
 ---
 
-## Q: How can I access events?
+### Q: How can I access the events which triggered the Reconciliation?
 In the v1.* version events were exposed to `Reconciler` (in v1 called `ResourceController`). This 
 included events (Create, Update) of the custom resource, but also events produced by Event Sources. After
 long discussions also with developers of golang version (controller-runtime), we decided to remove access to
 these events. We already advocated to not use events in the reconciliation logic, since events can be lost. 
 Instead reconcile all the resources on every execution of reconciliation. On first this might sound a little 
-opinionated, but there was a sound agreement between the developers that this is the way to go. 
+opinionated, but there was a sound agreement between the developers that this is the way to go.
+
+### Q: Can I re-schedule a reconciliation, possibly with a specific delay?
+Yes, this can be done using [`UpdateControl`](https://github.com/java-operator-sdk/java-operator-sdk/blob/main/operator-framework-core/src/main/java/io/javaoperatorsdk/operator/api/reconciler/UpdateControl.java) and [`DeleteControl`](https://github.com/java-operator-sdk/java-operator-sdk/blob/main/operator-framework-core/src/main/java/io/javaoperatorsdk/operator/api/reconciler/DeleteControl.java)
+, see:
+
+```java 
+  @Override
+  public UpdateControl<MyCustomResource> reconcile(
+     EventSourceTestCustomResource resource, Context context) {
+    ...
+    return UpdateControl.updateStatus(resource).rescheduleAfter(10, TimeUnit.SECONDS);
+  }
+```
+
+without an update:
+
+```java 
+  @Override
+  public UpdateControl<MyCustomResource> reconcile(
+     EventSourceTestCustomResource resource, Context context) {
+    ...
+    return UpdateControl.<MyCustomResource>noUpdate().rescheduleAfter(10, TimeUnit.SECONDS);
+  }
+```
+
+Although you might consider using `EventSources`, to handle reconciliation triggering in a smarter way.