Business & farm

Some comments regarding your question and situation:

• You don't just "become" a day trader.  There is no statute or election to reach this status.  This is a facts and circumstances test.  
• Trading securities has what I will call 3 levels
  • investor status
  • trader tax status (TTS)
  • TTS with a mark-to-market election (MTM)
• A taxpayer must be a qualified trader (TTS) in order to be eligible to make the MTM election
• Should you qualify for TTS, which I will not go into details in this thread, and you wanted to make the MTM election for 2021, you would have needed to file an election by the original due date for your 2020 tax return.  While the normal due date is April 15th, the IRS extended the due date to May 17, 2021.  
• In addition, you will need to file a form 3115 and include a copy of this with your 2021 form 1040.  This is an automatic change in accounting.
• In addition to filing the form 3115 with your tax return, you will also need to send a copy of the form 3115 to the IRS National office.  There is no user fee for this method of accounting change request; it is automatic.
• We will not be able to answer whether or not the IRS will agree that you were a qualified TTS since as stated above, this is very much facts and circumstances.
• Revocation of MTM is a reverse mirror of the original election.  Once revoked, a taxpayer cannot re-elect for 5 years after revocation.
• As noted above, in order to qualify for MTM, a taxpayer must be a qualified trader (TTS).  Once you no longer qualify for TTS, a taxpayer is no longer eligible to use the MTM; you are now just an investor and are not eligible for the MTM.  As a result, the MTM status is essentially "suspended" until such time as the taxpayer once again qualifies for TTS.
• So technically you have two options; a complete revocation or the alternate "suspension"
• This is a tricky area and one fraught with costly errors if you are not familiar with all of the technicalities.
• This is an area where a tax professional, one that understands this area, should be consulted.