This support article contains a link to the UPS website where you can type in your Ship From and Ship To addresses to confirm the classes of service available for certain shipments in Lead Commerce.

https://wwwapps.ups.com/ctc/request

Use that line above to see directly from UPS what classes of service are available.

IMPORTANT THINGS TO CONSIDER:
Sometimes classes of service for UPS might appear one day and then not be available on another day. This can be caused by delays within the UPS infrastructure, weather patterns, airport delays, etc.