I need some tips or suggestions to make this plug-in faster.

My concerns are:

1. Option below the address section: "Shipping Address, Same as Billing?". If I checked it or unchecked, this page takes about 3-4s to load. That is too slow. Is there a better way to improve it to make it faster?

2. I'm still using the "latest" Fedex plug-in I downloaded from zen cart. Version 1.5.4 which is released in 2016. Its author is numinix. I went to their website and found the latest module version 1.8.1 which is released in 2021. I tried it and it seems 200-300ms faster than the old version. But some times, I can still see the pop-up "It's taking a little longer than normal to update your order's shipping cost." I understand that every time when I changed my shipping address, zen cart will get a new shipping quote from shipping carrier API. With this plug-in, I can already see all the shipping quote for different methods. But every time when I choose a different shipping method, can I just use the value from the current quote result or pre-loaded quote data, not get a new quote from the shipping carrier API? That is just my thought to speed-up. Not sure if it is possible or not.