Three silly little clues leave me feeling incomplete!!
30A What's stranded in port maybe after end of shift (5) T-I-E
50D Flower Queen darling taking the year off (5) R_O_E
52D Mass invasion of pitch by any umber (%) T_N_E
Thanks to you both for these answers. TWINE and TONNE seem completely logical but RHONE is on less firm ground unless it refers to the crimson poppies known as Bouches du Rhone!, which is somewhat distant.....