How OPNSense know which Intermediate cert to use

[Creator_1995]

Hello everyone,

I have one question that really puzzles me.
Here is my setup.

In System/Trust/Authorities I have two Let's encrypt Intermediate certificates that I imported for use. One is the R3 certificate that will be valid until 2021/09/21 and the newly imported E1 certificate that will be valid until 2025.
After I click renew the certificate, in Services/Let'sEncrypt/Certificates I am presented with the new certificate that has R3 as an issuer. 

My question is the following. How I can tell Lets'encrypt service that I need a new certificate with an E1 intermediate certificate as an issuer?