Avoid dehydration that makes HTC worse. For fasting lab work, do not get dehydrated.
Avoid iron fortified foods: rice, bread, flour, cereals and vitamins. Read the labels.
Improve blood flow with mini aspirin and fish oil.
The problem is reduced blood flow in vascular organs and the brain. Reduced blood flow in kidneys increases EPO that increases red cell production. At altitude some of that effect is there already [potentially making things worse].
"it is stimulated by decreased O2 in circulation, which is detected by the kidneys"
So you can get into a self-escalating problem.
With high HTC, you can be rejected as a blood doner as a disease risk factor.
You do not test E2?
T spikes from weekly injections may make things worse. Subq injections twice a week would be better.