If you downgrade your insurance for your extension term, be aware that you will go from $500,000 worth of coverage per incident to only $100,000 coverage per illness. You will also need to pay a $50 deductible every time you see a doctor in addition to a 20% co-pay for the cost of treatment. This can amount to quite a bit of money. Also, you will not have insurance for your travel month, which you will need to purchase if you decide to stay in the US for all or part of your travel month.
Please send me an email saying that you understand the differences in medical coverage between the upgrade plan you had in your first year and the downgraded basic coverage and you agree to the terms of the basic insurance.