We are regular theatre goers, to get good seats you sometimes have to book 12 months in advance. I am currently juggling 14 theatre/concert bookings and every one has been rearranged once, most twice and one three times, I now have to keep a spreadsheet to see where, when original date, what is revised date, if revised date clashes with anything else, if tickets are to be reissued or originals are still valid.
Nightmare.