You will get the option to sync assessment plan when you:
Add an assessment
Remove an assessment
Change the weights assigned to existing assessments
The above changes can be made to an assessment plan through Courses → Manage Courses → Edit Course → Assessment Plan. An option to sync the changes made in the assessment plan will appear as shown in the screenshot below.
Once done, select the batch for which you intend to sync the assessment plan.
You can check the “Select all” box in order to select all the batches.
Once done, click on the “Sync” button
Once sync is complete, you will receive an email confirming the same.