If you see a shop on the job board that you would like to conduct and do not see any available dates on the calendar this could mean several things:
1. Another shopper may have taken the shop.
2. Some clients require shopper rotation (IE - every 3 months) and you conducted a shop last month. In this case you will not see any available dates.
3. The client may have requested that you no longer provide services for their project. This happens from time to time if guidelines were not followed, if the report was not correctly filled out, fraud, etc. This is why it's very important to ensure you read the guidelines and survey BEFORE you conduct the shop.
4. You might not have the qualifications required to provide services to the client. (compliance shops).