https://github.com/nightscout/AndroidAPS/issues/5307

Author: psonnera

docs/EN/DailyLifeWithAaps/AapsScreens.md

@@ -718,7 +718,7 @@ Like most of these rules-of-thumb it is of limited real validity. Note: Your dia
 
 ![Insulin screen](../images/manage/insulin_profile.png)
 
-**Manage → Insulin settings** shows and manages your insulin configurations. The active configuration with its **peak time** and **[DIA](#Config-Builder-insulin-dia)** is shown on a card; below it you can edit the nickname, peak and DIA, and see the activity curve.
+**Manage → Insulin settings** shows and manages your insulin configurations. Each configuration is shown on a card with its **peak time** and **[DIA](#Config-Builder-insulin-dia)**; the one in use is marked **ACTIVE**. Below the card you see the activity curve. You can edit the nickname, peak and DIA of any configuration except the active one: to change the insulin you are using, [add a new configuration and activate it](#Config-Builder-insulin-change-active).
 
 See [Config Builder > Insulin > Duration of insulin action](#Config-Builder-insulin-dia) to learn more about what it is and how to set it.
 

docs/EN/Maintenance/V4Changes.md

@@ -91,6 +91,20 @@ If you don't need to protect your settings, you can turn Settings protection off
 
 ---
 
+(v4changes-active-insulin)=
+## The insulin in use can't be edited
+
+In **AAPS** v3, you could change the DIA of the insulin you were using at any time.
+
+In **AAPS** v4, the insulin marked **ACTIVE** in **Manage → Insulin settings** is greyed out: you cannot edit or delete it.
+
+```{admonition} What you need to do
+:class: important
+To change the DIA or peak, add a new insulin with **+**, adjust it, save it and **▶ Activate** it. See [Changing the insulin in use](#Config-Builder-insulin-change-active).
+```
+
+---
+
 (v4changes-remote-control)=
 ## AAPSClient remote control needs pairing
 

docs/EN/SettingUpAaps/ConfigBuilder.md

@@ -86,6 +86,25 @@ The **IOB** (insulin on board) and **Activity** curves shown at the bottom of th
 
 More information to understand the Insulin Profile as shown in **AAPS** [here](#AapsScreens-insulin-profile).
 
+(Config-Builder-insulin-change-active)=
+### Changing the insulin in use (DIA or peak)
+
+The insulin marked **ACTIVE** is the one your running profile uses. Its fields are greyed out: you cannot edit or delete it. This way, the insulin name shown in your running profile always matches the settings actually in use.
+
+To change the DIA or peak you are using:
+
+1. Open **Manage → Insulin settings**. If the screen opens read-only (a **✏️ pencil** in the top bar), tap the pencil and unlock your settings.
+2. Tap **+** (_Add new insulin_). **AAPS** creates a copy of the insulin shown on screen.
+3. Set the new **Peak** and/or **DIA**, then tap the save icon (top right).
+4. Tap **▶** (_Activate insulin_) and confirm. The new insulin becomes **ACTIVE**.
+
+```{admonition} The name includes peak and DIA
+:class: note
+**AAPS** adds the peak, DIA and concentration to the insulin name automatically (for example _Fiasp 55m 8h U100_), so you can tell your configurations apart at a glance.
+```
+
+You can delete the old insulin once it is no longer active.
+
 ### Insulin type differences
 
 * The options 'Rapid-Acting Oref', 'Ultra-Rapid Oref', 'Lyumjev' and 'Free-Peak Oref' all have an exponential curve.