Clothing Damage: After the Turtles and Renet have been in the Cretaceous period for 3 months their outfits and accessories are falling apart and have been patched up with locally sourced materials.
Compressed Hair: Underneath Renet's costume we discover she has waist-length blonde hair. Even accounting for 3 months growth, her hair should be far too long to fit snugly under her blue skin-tight head-piece
Delaying Action: Raph, Don and Mikey keep Savanti busy so don can rescue Renet and the Time Scepter
Dropped a Bridge on Him: Discussed. When Donatello projects they have two or three months before it hits, Leonardo laments going out like that after all their adventures.