I've been continuing with my litre of skimmed milk a day plan and feel better for it and have also been making sure I'm eating more than enough carbohydrates. I reckon I'll not worry about my weight too much for the moment until such time as I start to feel a bit more like my old self.
The good news is that the plan seems to be working and I've been feeling considerably better today, done some shopping (more TdF DVDs!) and even some gardening and the time came this evening to do a spell on the turbo to see how things were going.
Did a steady hour on the CompuTrainer and immediately knew that I was feeling a whole lot better, the fatigue is on it's way out of my legs and I felt much stronger. I rode keeping my HR at all times below 150 and below 130 for the vast majority of the time. I just went up to 150 quite briefly a couple of times just to see what the corresponding power output was and was pretty pleased, it's coming back. At 150BPM my power output was 285W and at the upper limit of my HR zone 2 (138BPM) the output was 250W so those figures are much more in line with where I was recently. Did glance back at my output at 150BPM a month ago and it was measured at about 245 so if that's right that's encouraging, I must check in more detail.
So, long ride tomorrow and feel more confident about it after today and after the large bowl of pasta I've just eaten!