1a) Former PM hosted a short party using a mobile home (11)
1d) 100 old British gents ended up on ship, showing cruelty (4-11)
4d) Note adult lovelorn travellers who enjoy full exposure (9)
7d) On which 27 (have got 27 yet) may start with optimism? (6)
18d) It's appropriate when birds get upset (6)
Apology for having no letters. All help greatly appreciated.