Hi Sarah, well done on getting selected to have a mentor for your goal. I've read through this thread and looking at your short distance times it appears that you obviously tail off the longer you go. I'm sure with a larger endurance base you will hit your sub 3.30 goal.
I live in Sheffield and will be at BM in Jan. My husband works in Doncaster and has done the Maltby 10 back in the day
I have also done East Hull 20 a couple of times, once as a training run and once to achieve a time to try and top my age rankings for the year I did it, but did leave my marathon at that race and the 3 other 20 races before it, so agree do it, but keep it at training pace. A good way to run a 20 'race' is to either do it progressive, I've done it this way before where I started off with 5 miles easy, then increased my pace every 5 miles until I was running the final 5 miles at MP or marathon effort as MP is hard to hit until marathon day! Another way of running a 20 is to run the first 17 at normal long slow run pace then run the final 3 miles at MP/effort which will help to build your lactate threshold.
I have a treadmill at home and find it invaluable when the weather is so bad running outside becomes dangerous, not often, but since moving to Yorkshire I have had days where the treadmill was the only option and I'd rather run on that than not at all. Also, will use the gym one, but again would prefer to run outside, but agree with you that running in the dark is sometimes not an option. I've trained on it on and off for years and it's not prevented me hitting my marathon target, in fact it's very good mental preparation running 16+ miles on there!
I will pop in from time to time and see how you're progressing. So many good threads on Spring Marathon at the minute
Edited: 24/12/2012 at 19:19
