Historical clue formulations

• Former title for 16-Across: Abbr. — 2024-03-28
• Monarch's inits. — 2019-11-03
• Regal initialism — 2018-10-09
• Prince's inits. — 2015-11-22
• Letters for a prince — 2014-06-17
• Title for a princess: Abbr. — 2014-05-13
• Letters for a princess — 2012-12-28
• Princely inits. — 2012-09-04
• Letters for a prince or princess — 2011-12-20
• Princely abbr. — 2011-06-05
• Prince's title: Abbr. — 2010-12-06
• Regal letters — 2010-10-03
• Danielle Steel novel about a European princess — 2010-08-29
• Letters for a duke — 2010-07-17
• Title for a prince or princess: Abbr. — 2010-05-31
• Buckingham Palace letters — 2009-12-23
• Regal inits. — 2009-08-23
• Initials for Camilla — 2008-06-04
• Regal inits. — 2007-02-20
• Buckingham Palace inits. — 2004-09-05
• Letters of royalty — 2004-08-20
• Princely initials — 2003-07-29
• Letters for a prince — 2001-02-25
• Queen Eliz., e.g. — 1999-02-28
• Initials for a prince — 1998-09-30
• Royal initials — 1996-04-29