Um… multiple locations (Ron had taken something to let him recover/reuse fast), which meant four separate sets of citations. The “cleaner” version of the story lets the reader construct the date from Harry listing the citations, while the “explicit” version shows the date details Thus for citations 3 & 4:
“Ought to demand a refund,” Harry said, “Clearly an all–you–can–eat buffet should include a free banger.”
“Aw,” Harry said, “Guess the opera didn’t appreciate you two climaxing at their climax.”