DOCSP-48100: Consolidate 2.x versions (#239)

* DOCSP-48100: Consolidate 2.x versions

* revert redirects

* edits

* stage

* word

Author: norareidy

snooty.toml

@@ -50,3 +50,4 @@ api = "https://www.mongodb.com/docs/php-library/current/reference"
 string-data-type = "``string``"
 bool-data-type = "``bool``"
 int-data-type = "``int``"
+language = "PHP"

source/upgrade.txt

@@ -30,15 +30,16 @@ How to Upgrade
 
 Before you upgrade, perform the following actions:
 
-- Ensure the new {+library-short+} version is compatible with the {+mdb-server+} versions
-  your application connects to and the PHP version your
-  application compiles with. For version compatibility information, see the
-  :ref:`{+php-library+} Compatibility <php-compatibility>`
-  page.
 - Address any breaking changes between the library version
   your application is using and your planned upgrade version in the
   :ref:`Breaking Changes <php-breaking-changes>` section.
 
+- Ensure the new {+library-short+} version is compatible with the {+mdb-server+} versions
+  your application connects to and the PHP version your
+  application compiles with. For version compatibility information, see the
+  :ref:`Compatibility Changes <php-compat-changes>` section and the 
+  :ref:`{+php-library+} Compatibility <php-compatibility>` page.
+
 .. tip::
 
    To ensure compatibility across {+mdb-server+} versions when
@@ -81,8 +82,9 @@ application from working properly if not addressed before upgrading the
 library.
 
 The breaking changes in this section are categorized by the library
-version that introduced them. When upgrading library versions, address
-all the breaking changes between the current and upgrade versions.
+version that introduced them. Only major library versions introduce
+breaking changes. When upgrading versions, address all
+the breaking changes between the current and upgrade versions.
 
 For more information on release changes, see the release notes and
 associated JIRA tickets for each release on `GitHub
@@ -113,15 +115,23 @@ This library version introduces the following breaking changes:
   methods, you can register a :php:`CommandSubscriber
   <mongodb-driver-monitoring-commandsubscriber>` in your application.
 
-Version 1.20 Breaking Changes
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+.. _php-compat-changes:
 
-This library version introduces the following breaking changes:
+Compatibility Changes
+---------------------
+
+This section describes the {+mdb-server+} and {+language+} compatibility
+changes introduced in {+php-library+} version releases.
+
+Version 1.x Compatibility Changes
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+This library version introduces the following compatibility changes:
 
-- Drops support for {+mdb-server+} 3.6.
+- Drops support for {+mdb-server+} 3.6 in {+php-library+} v1.20
 
-Version 1.19 and Earlier
-~~~~~~~~~~~~~~~~~~~~~~~~
+.. tip:: Earlier Library Versions
 
-For library versions 1.19 and earlier, see the release notes and associated 
-JIRA tickets for each release on `GitHub <https://github.com/mongodb/mongo-php-library/releases>`__.  
+   To view compatibility changes for {+php-library+} versions 1.19 and earlier, see the
+   release notes and associated JIRA tickets for each release on `GitHub
+   <https://github.com/mongodb/mongo-php-library/releases>`__.