diff --git a/recipes/recipe_modules/bot_update/resources/bot_update.py b/recipes/recipe_modules/bot_update/resources/bot_update.py
index 9d02506..6213714 100755
--- a/recipes/recipe_modules/bot_update/resources/bot_update.py
+++ b/recipes/recipe_modules/bot_update/resources/bot_update.py
@@ -839,7 +839,8 @@
   return None
 
 
-def parse_got_revision(gclient_output, got_revision_mapping):
+def parse_got_revision(gclient_output, got_revision_mapping,
+                       prev_checkout_info):
   """Translate git gclient revision mapping to build properties."""
   properties = {}
   solutions_output = {
@@ -862,9 +863,16 @@
       revision = git('rev-parse', 'HEAD', cwd=dir_name).strip()
       commit_position = get_commit_position(dir_name)
 
+    prev_revision, prev_cp = prev_checkout_info.get(dir_name.rstrip('/'),
+                                                    (None, None))
+
     properties[property_name] = revision
+    if prev_revision:
+      properties['prev_%s' % property_name] = prev_revision
     if commit_position:
       properties['%s_cp' % property_name] = commit_position
+    if prev_cp:
+      properties['prev_%s_cp' % property_name] = prev_cp
 
   return properties
 
@@ -1105,6 +1113,16 @@
   print('Fetching Git checkout at %s@%s' % (first_sln, revisions[first_sln]))
   return revisions, step_text
 
+def current_checkout_info(solutions):
+  r = {}
+  build_dir = os.getcwd()
+
+  for sln in solutions:
+    sln_dir = path.join(build_dir, sln['name'])
+    if path.isdir(sln_dir) and not is_broken_repo_dir(sln_dir):
+      r[sln['name']] = (git('rev-parse', 'HEAD', cwd=sln_dir).strip(),
+                        get_commit_position(sln_dir))
+  return r
 
 def checkout(options, git_slns, specs, revisions, step_text):
   print('Using Python version: %s' % (sys.version,))
@@ -1128,6 +1146,8 @@
     # create file, no content
     pass
 
+  prev_checkout_info = current_checkout_info(git_slns)
+
   should_delete_dirty_file = False
 
   try:
@@ -1201,7 +1221,8 @@
   if not revision_mapping:
     revision_mapping['got_revision'] = first_sln
 
-  got_revisions = parse_got_revision(gclient_output, revision_mapping)
+  got_revisions = parse_got_revision(gclient_output, revision_mapping,
+                                     prev_checkout_info)
 
   if not got_revisions:
     # TODO(hinoka): We should probably bail out here, but in the interest