So, here's what the week held for me...
I did the schedule as planned. On Saturday I did 1 hour 40 as it was exactly 16km and ended not far from my flat, so I just stopped then. It was a 6.17km with an AvHr of 153bpm. I found it okay, a little laborious but generally comfortable. My legs were a bit stiff afterwards so on Sunday I just jumped on the bike for a while instead of the proscribed 30 mins easy run.
I did the Monday easy 30 mins and then tonight (Tuesday) I did the 6x1km with a target of 5.20. Here's the times and heart rates.
5:06 - 145bpm
5:03 - 160bpm
5:01 - 152bpm
5:07 - 152bpm
5:02 - 154bpm
5:06 - 155bpm
I took a 60 second break the first time and then took 90 seconds for the rest of them as I thought I wouldn't have made it if I had only taken 60 seconds per break.
I was in a strange mood for this run as I was very tired (so much so I had to take a half an hour nap before I headed out for this session) but I did eat well and hydrated well during the day and I felt I probably could have done maybe another 2kms under the 5:20 after this. As I said, it was a weird one. Glad to be able to post good times though, so I'm very happy with myself. (And for sticking it easily enough!)
What should my target be now for Saturdays 5km run?
Thanks for the feedback, it keeps me encouraged to stick at this.