In General
— Use periods between a.m. and p.m. (also use lowercase)
— This requirement may be waived when space constraints are an issue; in these instances, use AM or PM
— Use plain date number, no English suffix (no 1st, 2nd, 14th, etc.)
— Use a dash (en dash (–) if possible) between start & end times, with spaces between the numbers and the dash (7:00 – 9:00 p.m.)
— Decades: do not use apostrophes between the letter “s” and numbers (1920s or ’20s, not 1920’s)