There are also shorter maintenance fix-ups called "availabilities" for ships periodically at shipyards. Depending on equipment and player's availabilities, pond hockey may or may not use a goalie. The ultimate length equals the maximum length at high food availabilities. The ship went through four Continuous Maintenance Availabilities (CMAVs) in April, June, September, and November. Among the ships for which "Vulcan" provided availabilities was the intelligence ship . The need for buildings far surpassed the availabilities. Hewlett wrote the script especially around those availabilities. It was due to the lack of player availabilities.