diff --git a/mailing/migrations/0003_auto_20171129_2155.py b/mailing/migrations/0003_auto_20171129_2155.py
index 9d7ae61..d3a8a0e 100644
--- a/mailing/migrations/0003_auto_20171129_2155.py
+++ b/mailing/migrations/0003_auto_20171129_2155.py
@@ -7,32 +7,6 @@ import django.db.models.deletion
 import mailing.models
 
 
-def forward(apps, schema_editor):
-    db_alias = schema_editor.connection.alias
-    Message = apps.get_model("mailing", "Message")
-    MessageAuthor = apps.get_model("mailing", "MessageAuthor")
-    for message in Message.objects.using(db_alias).all():
-        message.new_author, _ = MessageAuthor.objects.using(db_alias).get_or_create(author_type=message.author_type, author_id=message.author_id)
-        message.save()
-
-
-def backward(apps, schema_editor):
-    db_alias = schema_editor.connection.alias
-    Message = apps.get_model("mailing", "Message")
-    ContentType = apps.get_model("contenttypes", "ContentType")
-    for message in Message.objects.using(db_alias).all():
-        author_type = message.new_author.author_type
-        message.author_type = message.new_author.author_type
-        message.author_id = message.new_author.author_id
-        AuthorType = apps.get_model(author_type.app_label, author_type.model)
-        author = AuthorType.objects.get(pk=message.author_id)
-        if author_type.model == 'conference':
-            message.from_email = author.contact_email
-        else:
-            message.from_email = author.email
-        message.save()
-
-
 class Migration(migrations.Migration):
 
     dependencies = [
@@ -61,37 +35,4 @@ class Migration(migrations.Migration):
             name='from_email',
             field=models.EmailField(blank=True, null=True),
         ),
-        migrations.RunPython(forward, backward),
-        migrations.RemoveField(
-            model_name='message',
-            name='author_id',
-        ),
-        migrations.RemoveField(
-            model_name='message',
-            name='author_type',
-        ),
-        migrations.RemoveField(
-            model_name='message',
-            name='from_email',
-        ),
-        migrations.RenameField(
-            model_name='message',
-            old_name='new_author',
-            new_name='author',
-        ),
-        migrations.AlterField(
-            model_name='message',
-            name='author',
-            field=models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, to='mailing.MessageAuthor'),
-        ),
-        migrations.AddField(
-            model_name='message',
-            name='in_reply_to',
-            field=models.ForeignKey(blank=True, null=True, on_delete=django.db.models.deletion.CASCADE, to='mailing.Message'),
-        ),
-        migrations.AddField(
-            model_name='message',
-            name='subject',
-            field=models.CharField(blank=True, max_length=1000),
-        ),
     ]
diff --git a/mailing/migrations/0004_auto_20171130_2034.py b/mailing/migrations/0004_auto_20171130_2034.py
new file mode 100644
index 0000000..da2d3b6
--- /dev/null
+++ b/mailing/migrations/0004_auto_20171130_2034.py
@@ -0,0 +1,42 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.11.1 on 2017-11-30 20:34
+from __future__ import unicode_literals
+
+from django.db import migrations
+
+
+def forward(apps, schema_editor):
+    db_alias = schema_editor.connection.alias
+    Message = apps.get_model("mailing", "Message")
+    MessageAuthor = apps.get_model("mailing", "MessageAuthor")
+    for message in Message.objects.using(db_alias).all():
+        message.new_author, _ = MessageAuthor.objects.using(db_alias).get_or_create(author_type=message.author_type, author_id=message.author_id)
+        message.save()
+
+
+def backward(apps, schema_editor):
+    db_alias = schema_editor.connection.alias
+    Message = apps.get_model("mailing", "Message")
+    ContentType = apps.get_model("contenttypes", "ContentType")
+    for message in Message.objects.using(db_alias).all():
+        author_type = message.new_author.author_type
+        message.author_type = message.new_author.author_type
+        message.author_id = message.new_author.author_id
+        AuthorType = apps.get_model(author_type.app_label, author_type.model)
+        author = AuthorType.objects.get(pk=message.author_id)
+        if author_type.model == 'conference':
+            message.from_email = author.contact_email
+        else:
+            message.from_email = author.email
+        message.save()
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('mailing', '0003_auto_20171129_2155'),
+    ]
+
+    operations = [
+        migrations.RunPython(forward, backward),
+    ]
diff --git a/mailing/migrations/0005_auto_20171130_2039.py b/mailing/migrations/0005_auto_20171130_2039.py
new file mode 100644
index 0000000..94b5033
--- /dev/null
+++ b/mailing/migrations/0005_auto_20171130_2039.py
@@ -0,0 +1,48 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.11.1 on 2017-11-30 20:39
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('mailing', '0004_auto_20171130_2034'),
+    ]
+
+    operations = [
+        migrations.RemoveField(
+            model_name='message',
+            name='author_id',
+        ),
+        migrations.RemoveField(
+            model_name='message',
+            name='author_type',
+        ),
+        migrations.RemoveField(
+            model_name='message',
+            name='from_email',
+        ),
+        migrations.RenameField(
+            model_name='message',
+            old_name='new_author',
+            new_name='author',
+        ),
+        migrations.AlterField(
+            model_name='message',
+            name='author',
+            field=models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, to='mailing.MessageAuthor'),
+        ),
+        migrations.AddField(
+            model_name='message',
+            name='in_reply_to',
+            field=models.ForeignKey(blank=True, null=True, on_delete=django.db.models.deletion.CASCADE, to='mailing.Message'),
+        ),
+        migrations.AddField(
+            model_name='message',
+            name='subject',
+            field=models.CharField(blank=True, max_length=1000),
+        ),
+    ]