The previous version of SURF's object store service was based on OpenStack Swift, the current version is based on Ceph RGW. This page outlines the differences between the two.
Service endpoint
The URL for the service has changed to objectstore.surf.nl
S3 bucket region
The region for S3 connections has changed from 'NL' to 'Default' or 'default', depending on your client. Some clients work without specifying any region.
TempURL
The mechanism for generating TempURLs works differently. Please consult the documentation.