Clarifed FEFO Section

Reworded to improve English and clarity. Added additional language explicitly describing function of the four types of expiration dates. Added instructions for using time fields on product form for automation of expiration dates.

inventory/routes/strategies/removal.rst

@@ -11,7 +11,7 @@ control purpose or due to reason of product expiration.
 
 When a product movement needs to be done, Odoo will find available
 products that can be assigned to shipping. The way Odoo assign these
-products depend on the **removal strategy** that is defined on the **product
+products depend on the **removal strategy** that is defined on the **product 
 category** or on the **location**.
 
 Configuration
@@ -109,27 +109,52 @@ Then click on **Apply** to save changes.
 .. image:: media/removal08.png
     :align: center
 
-It will allow you to set **best before date**, **end of life date**, **alert
-date** and **removal date** on the serial number. Go to 
-:menuselection:`Inventory Control --> Serial Numbers/Lots`.
+This will allow you to set four expiration fields for each lot or serial number: 
+**best before date**, **end of life date**, **alert date** and **removal date**.
+These dates can be set from :menuselection:`Inventory Control --> Serial Numbers/Lots`.
 
 .. image:: media/removal09.png
     :align: center
 
 -   **Best Before Date**: This is the date on which the goods with this
-    serial number start deteriorating, without being dangerous yet.
+    serial/lot number start deteriorating, without being dangerous yet.
 
 -   **End of Life Date:** This is the date on which the goods with this
-    serial number may become dangerous and must not be consumed.
+    serial/lot number may become dangerous and must not be consumed.
 
 -   **Removal Date:** This is the date on which the goods with this
-    serial Number should be removed from the stock.
+    serial/lot number should be removed from the stock. Using the FEFO
+    removal strategym goods are picked for delivery orders using this date.
 
--   **Alert Date:** This is the date on which an alert should be notified
-    about the goods with this serial number.
+-   **Alert Date:** This is the date on which an alert should be sent
+    about the goods with this serial/lot number.
 
-Products will pick first with expiry date (removal date), So you have
-to set removal date on lot/serial numbers.
+Lots will be picked based on their **removal date**, from earliest 
+to latest. Lots without a removal date defined will be picked after 
+lots with removal dates.
+
+All dates except **removal date** are for informational and reporting purposes only. 
+Lots that are past any or all of the above expiration dates may still be picked 
+for delivery orders, and no alerts will be sent when lots pass their **alert date**.
+
+Expiration dates on lots can also be set automatically when goods are received into stock.
+After enabling expiration dates on serial numbers, four new fields will become available 
+in the inventory tab of the product form: **product life time**, **product use time**, 
+**product removal time**, and **product alert time**. When an integer is entered into one 
+of these fields, the expiration date of a lot/serial of the product in question will be set 
+to the creation date of the lot/serial number plus the number of days entered in the time
+increment field. If the time increment field is set to zero, then the expiration date of 
+a lot/serial must be defined manually after the lot has been created.
+
+Each of these time increment fields is used to generate one of the lot expiration date fields as follows:
+
+Product Use Time --> Best Before Date
+
+Product Removal Time --> Removal Date
+
+Product Life Time --> End of Life Date
+
+Product Alert Time --> Alert Date
 
 To set the removal strategy on location, go to 
 :menuselection:`Configuration --> Locations` and choose FEFO.