5/25/2021 Update: US Mail is still running behind in some cases, but transit times are much improved from the previous few months. If you need your diagram(s) quickly, please select UPS at checkout. We have negotiated a flat rate of $9.95 per shipment. (Residential & Extended Area surcharges are included) East of the Mississippi should receive items in 2-4 business days or less, rest of continental US in 4-6 business days at most. The Estimated Dates you see on the USPS site are not guaranteed. UPS dates on the other hand are pretty accurate.