Original issue test Repeat the tests in MDL-72350 and confirm that everything is still passing. Testing Create a new 4.1 instance and install it Make sure you turn on the debugging Insert invalid records into grade_items, grade_items and grade_items_history tables by running the following SQL INSERT INTO mdl_grade_items(id, itemtype, itemmodule) VALUES (101, 'mod' , 'assignment' ); The itemid exists in grade_items INSERT INTO mdl_grade_grades(itemid, userid) VALUES (101, 101); The itemid does not exists in grade_items INSERT INTO mdl_grade_grades(itemid, userid) VALUES (111, 101); INSERT INTO mdl_grade_items_history(oldid, itemtype, itemmodule) VALUES (101, 'mod' , 'assignment' ); Upgrade to 4.2 by checking out master branch Apply the patch Follow the upgrade process Verify that you don't see any warning or exception like the following screenshoot Verify that you don't see any records of mod_assignment in grade_items by running the following SQL SELECT * FROM mdl_grade_items WHERE itemtype = 'mod' AND itemmodule = 'assignment' ; Verify that you don't see any records of mod_assignment in grade_items_history by running the following SQL SELECT * FROM mdl_grade_items_history WHERE itemtype = 'mod' AND itemmodule = 'assignment' ; Verify that you don't see grade_grades record with itemid of "101" and orphaned grade items (itemid="111") from other components are not touched by the upgrade process by running the following SQL SELECT * FROM mdl_grade_grades WHERE itemid = 101 OR itemid = 111; Testing for 3rd party mod_assignment plugins: Install a fresh 4.1 instance Install a mod_assignment plugin e.g. assignment_uploadpdf Put the plugin files in mod/assignment/type/uploadpdf Check out the master branch and apply the patch Confirm that an "Assignment 2.2 subplugins present" error is shown on the environment check and that upgrade cannot continue. Remove the mod/assignment folder. Reload the page. Confirm that upgrade can proceed. Testing stable branches (39, 311 and 400). Install a MOODLE_XXX_STABLE site. Go to Admin -> Server -> Environment. Verify that there aren't errors related to Assignment 2.2 is in use . Install a mod_assignment plugin e.g. assignment_uploadpdf Put the plugin files in mod/assignment/type/uploadpdf Follow upgrade process Go to Site admin/Server/Environment In the "Moodle version" drop down, select "Moodle 4.2 and upwards". Verify that you see an error of Assignment 2.2 is in use If there are other versions in the "Moodle version" drop down... verify that only "4.2 and upwards" shows the error. Repeat all the steps above for the other branches.