Create and download PKCS#12 key pair file in communication arrangement: Extend validity date?

Dear experts,

we are configuring an inbound communication scenario in C4C which exposes a web service to be consumed by a partner.

As our partner cannot provide a public key certificate for certificate-based authentication we have created a PKCS#12 key pair in the communication arrangement for the respective communication system.

Validity period of the certificate seems to be one year. Is there any possibility to create a certificate / key-pair with an extended validity period which has a validity of several years?

Thank you for your advice!