42.
S1: My office sent an urgent email asking me to return.
S6: It was evening before I could sit and write to my parents that I would be joining them soon.
P: I immediately replied requesting a few days of grace as I had to book the return passage, pack and attend sundry matters before winding up my establishment here.
Q: On the way, I went to the laundry and made sure I would get my clothes in time.
R: Then I rushed to the bank, collected all my money and made reservations for my return journey.
S: From the shop next to it, I bought a couple of trunks to dump my books and other odd articles so that I could send them away in advance.
The proper sequence should be