Thanks for your quick response. I don't wish to add the burden to me and IRS' existing workload going through long waiting callings. As long as I still can complete my 2020 tax report while waiting for my 2019 tax refund and my stimulus checks that won't be missed, I can wait. Thanks for your information. It eased my worries. If it's stated clearly in public (getting the status 'cannot provide' or 'not available' is not really helping!) , it would help many people in my case and save many difficult calls, I think.
