this only affects SharePoint integrated mode. With SSRS native mode nothing is required to change.
On backup Subscription Manager saves the site name as a folder. Due to limitation of the file system certain characters cannot be used in the folder name / and : so the site name folder is to be translated.
: is replaced with @
/ is replaced with #
eg:
site name: http://sitename/sites
folder name: http@##sitename#sites
If you backup and restore on the same SharePoint server the URL will be the same.
If you restore to a different SharePoint server, the URL will be different. In this case you will need to rename the SharePoint site folder.
Example
Root backup folder is c:\ssrs
old SharePoint site name is http://oldServer:8080
the restore will be to the new SharePoint server- site name http://newserver
1. On backup the Excel files for report subscriptions will be created under the folder:
c:\ssrs\http@##oldServer@8080
2. Next rename the SharePoint site name folder to the new server SharePoint site name
rename folder http@##oldServer@8080 to http@##newserver
c:\ssrs\http@##newserver
3. Continue the Restore process