Several decades of LH has burnt out my body clock, I think. Occasionally I get a tired period during the middle of the day but most it’s about surviving nights out of bed. Strangely, I still can sleep 8-10hrs when given the opportunity but at work it can get a bit fragmented.
I have done 9-5 office jobs as well, and definitely felt a bit sleepy Friday afternoons, especially after a liquid lunch...