@sfrost
'Reprocessing assets' option is available on cloud - Assets as a cloud service.
Generally, SVG files render thumbnails upon upload, unless they are corrupted or there are system performance-related issues that may cause delays in processing. I have verified this behavior on Guides 4.0.2 UUID, and there have been no issues with thumbnail rendering. If the issue occurs occasionally, it may be necessary to check the logs for further investigation. Please let us know if you require any assistance!