Hard to say since the IRS processing centers are mostly shut down and incoming mail is being stored - not opened.
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**NOTE*** Due to the Corona virus the IRS is operating short staffed. All field offices are closed and some processing centers are all but closed. Any tax return that requires hand processing will probably have long delays. Mailed returns are not being processed at all at this time. Most phone service has been curtailed.
https://www.irs.gov/newsroom/irs-operations-during-covid-19-mission-critical-functions-continue
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