What time do you go to bed work days?
I would, assuming you're in bed after 9pm, pin the GH 45 minutes pre workout. On non-training days, before breakfast. I really believe your natural GH pulse from hitting the weight hard will be serious enough to complement the exogenous GH well. On the weekend training days I would do 45min pre workout.
I break my dosages up right now, I do 5iu before breakfast and 5iu pre training (assuming they are ~4 hours or more apart. If I'm AM training, I just do it all at once). But, when I run lower dosages I run it just like the above suggestion. I do not want to interfere with the natural GH pulse if I can avoid it. Assuming the GH doesn't make you lethargic, pre workout IMO is best.
Regarding the sleep benefit, I still feel as though I sleep better even if I don't pin it close to bed. I know guys who do pin it close to bed, and have had good results. My thinking is WHY cut out that natural pulse if you can avoid it, and reap the benefits of the pulse and the exogenous?