Going into effect April 3, 2022. Described as a "Nonstandard Fee and Dimension Noncompliance Fee." 
USPS Will Charge You More for This, Starting April 3
"The surcharges start at any package longer than 22 inches, with a $4 fee for any package that exceeds 22 inches in length but is less than 30 inches. For packages over 30 inches in length, the fee goes up to $15. You will also have to pay an additional $15 if your package is greater than 2 cubic feet in volume."

USPS Will Charge You More for This, Starting April 3
"The surcharges start at any package longer than 22 inches, with a $4 fee for any package that exceeds 22 inches in length but is less than 30 inches. For packages over 30 inches in length, the fee goes up to $15. You will also have to pay an additional $15 if your package is greater than 2 cubic feet in volume."