Amended returns take 3-4 months to process. Check here. https://www.irs.gov/filing/wheres-my-amended-return
You would only know they got it if you got a tracking number from the post office when you mailed it.
IRS Amended returns FAQ
Amended return frequently asked questions | Internal Revenue Service
As of January 2024 it says.....
The current processing time is more than 20 weeks for both paper and electronically filed amended returns.
Where's my Amended return?
Where's My Amended Return? | Internal Revenue Service
After arriving, your amendment should appear quickly in the "where's my amended return" report even if you mailed it.
By quickly, I mean one week, or maybe two.
@karissaashlock20
Reply back if this is, or is not, your experience.