.
This may cause the issues below when incrementing existing backup sets:
Incremental / Differential backup sets will not be able to append to backups sets created before the upgrade.
This is because the disk partition table has changed and drive 'C:' will no-longer have the same partition length. In addition, the new Windows 10 partition will not be included and this is required for a system backup.
Solution:
Reflect will handle this automatically by creating a new full backup. However, this will not include the new Windows 10 partition. You should modify your XML definition to include this new partition to ensure that you can recover your system successfully.
Depending on your retention settings you may notice that Retention does not behave as expected
In the Macrium Reflect Defaults there is an option under the Backup settings called Retention Rules. Where it says "Retention Rules Apply To", if you have this set to Similar backup sets in the target folder, then new backups created post-Windows 10 upgrade may not be purged as the new backups look to be dissimilar i.e. from a different source.
Solution:
Where it says "Retention Rules Apply To" you can change the option to All backup sets in the target folder. This option determines how Reflect handles retention conflicts when you have backups from different sources going to the same target folder (which is effectively what has happened here with the resizing of the C: partition). By changing the setting you can have retention purge image files in that folder regardless of the data the image backups contain.
Use your judgement as to which option is right for you. It may be simpler to delete the old backups manually.