Possible Clues:

• A worker covering small hospital department for a skiver
• Teacher's concern
• Told to go into a communal meeting? One didn't
• One missing tea's been out
• A person who is not present
• Section of hospital in York, say, goes after Jack who's skiving?
• Not present with sailor to report scent of blue-green algae at centre
• Truant, badly beaten, keeps bearings
• Sailor dispatched over limitless reef one's failed to show up
• Ballot mailer