According to the USPS press release that I received on 9-3-21, the temporary rate increase will go into effect at 12:00 a.m., Central Time, on Oct. 3, 2021, and remain in place until 12:00 a.m., Central Time, Dec. 26, 2021. (So, yes, this includes all of your holiday season USPS parcels). 

*NOTE:  Here at BigBrandWholesale.com WE SHIP FOR FREE inside the USA, meaning you will not pay us any additional money for this rate increase.  We will deal with the increase on our own.  But if you are an online seller here is how much more you will have to pay to ship your buyers parcels:

The planned price changes include:

Priority Mail, Priority Mail Express, Parcel Select Ground and USPS Retail Ground:

• $0.75 increase for PM and PME Flat Rate Boxes and Envelopes.
• $0.25 increase for Zones 1-4, 0-10 lbs.
• $0.75 increase for Zones 5-9, 0-10 lbs.
• $1.50 increase for Zones 1-4, 11-20 lbs.
• $3.00 increase for Zones 5-9, 11-20lbs.
• $2.50 increase for Zones 1-4, 21-70 lbs.
• $5.00 increase for Zones 5-9, 21-70 lbs.

Additionally: