diff --git a/hr_payroll_timesheet/__init__.py b/hr_payroll_timesheet/__init__.py
index 0650744f..a16151af 100644
--- a/hr_payroll_timesheet/__init__.py
+++ b/hr_payroll_timesheet/__init__.py
@@ -1 +1,19 @@
 from . import models
+
+
+def ts_payroll_pre_init_hook(cr):
+    """
+    This module installs a Work Entry Type with code "TS"
+    If you have undergone a migration (either for this module
+    or even your own Payslip Work Entry lines with code "TS")
+    then the uniqueness constraint will prevent this module
+    from installing.
+    """
+    cr.execute("UPDATE hr_work_entry_type "
+               "SET code = 'TS-PRE-INSTALL' "
+               "WHERE code = 'TS';"
+               )
+    cr.execute("UPDATE hr_work_entry_type "
+               "SET code = 'TS_OT-PRE-INSTALL' "
+               "WHERE code = 'TS_OT';"
+               )
diff --git a/hr_payroll_timesheet/__manifest__.py b/hr_payroll_timesheet/__manifest__.py
index ebdaba8c..cb8baa6f 100755
--- a/hr_payroll_timesheet/__manifest__.py
+++ b/hr_payroll_timesheet/__manifest__.py
@@ -16,4 +16,5 @@
         'hr_timesheet',
         'hr_payroll_overtime',
     ],
+    'pre_init_hook': 'ts_payroll_pre_init_hook',
 }
diff --git a/hr_payroll_timesheet/migrations/13.0.0.0.1/pre-migration.py b/hr_payroll_timesheet/migrations/13.0.0.0.1/pre-migration.py
new file mode 100644
index 00000000..30a761b3
--- /dev/null
+++ b/hr_payroll_timesheet/migrations/13.0.0.0.1/pre-migration.py
@@ -0,0 +1,6 @@
+
+def migrate(cr, version):
+    # pre_init_hook script only runs on install,
+    # if you're coming from 12.0 we need the same change
+    from odoo.addons.hr_payroll_timesheet import ts_payroll_pre_init_hook
+    ts_payroll_pre_init_hook(cr)