Two things to note:

Elections (even national ones) are managed by the state. Contact the Secretary of State and ask what Oregon is doing to ensure that all ballots are received and counted. States get to make these decisions, not the federal government.

Messing with the mail is a federal crime. State Attorney Generals can go after Post Master Dejoy and the Trump administration for endangering people's lives and livelihoods by destroying the Postal Service. Some State AG's are already on this. Contact Oregon's AG, Ellen Rosenblum, and demand that an investigation and lawsuit be brought against DeJoy and the Trump administration for the federal crime of tampering with the mail.

Extras: Contact your congressional representatives in the House and ask articles of impeachment be drafted against DeJoy and Trump for the federal crime of tampering with the mail. Trump can be impeached again (and again and again and again, for all of his crimes) and that impeachment stands, even if the criminally corrupt and complicit GOP led Senate refuse to remove him from office. DeJoy can also be impeached and removed from his positions.

This is about people not getting their mail.
This is about people not getting their medications.
This is about people not getting their income.
This is about people not being able to run their businesses.
This is about people not being able to pay their bills.

Anyone believing this is normal, this does not affect Republicans JUST AS MUCH IF NOT MORE than it does Democrats, that this is not something every single person needs to be making serious noise about from now until it is stopped and the criminals held accountable is mistaken. This is not okay. This is not normal. This is not acceptable. This must be stopped.

Jesus, learn how to read. From the linked article,
“However, the update goes one step further, suggesting that people who have recovered are protected from getting sick again for at least three months.

The guidance is based on studies that found that, after three months, there was no evidence of people getting re-infected after recovering, a CDC official said. Longer-term studies are needed to determine how long protection might last, and it's still too soon to say to whether a person who has had COVID-19 and recovered is immune.”

Safe from reinfection for AT LEAST three months, not ABOUT three months. And the piece goes on to state that evidence of reinfection occurring has not been show.