Someone else may have mentioned it Andrew and you may have considered it before, but it's too late to trawl through, so here goes...
Is there any correlation with mileage completed the day before? I never used to worry too much about recovery but since realising that after my usual 60-80 (summer miles) on a Sunday, I'd be a calorie hunting monster the next day, I took it much more seriously. I'd often eat enough after a ride but still feel ravenous the next day and sometimes wanting fry-ups, subway sarnies and all the things my brain associates with cheap, cheerful protein and carb fixes whilst I'm not at home.
Since using a good recovery formula - 50-65g of whey protein, 2 x teaspoonfuls of spirulina in a pint of rice or oat milk being my own preference, I fare a lot better BUT...I do eat a fair amount of red meat too...? During the summer I was averaging around 200 miles a week and whilst the mileage is lower now (50 on the road and another 50 on the turbo during winter) if the sessions indoors on the turbo are intense enough, I sometimes take a half of the amounts above so I don't wake up and go the next day feeling I need to pile on the calories.
It would appear to me that your body is telling you that it needs more of something given the excess work it does for you on the bike...it's just a matter of finding what might fix the problem.
