As of June 1, 2021, and in compliance with the CA/Browser Forum Code-signing Baseline Requirements, Sectigo will require RSA keys to be a minimum of 3072 bits in size.
When generating keys and CSRs for code-signing certificates, please ensure you choose an RSA key with a 3072- or 4096-bit key size.
Only the size of the keys is to change, the rest of the process remains the same. Existing RSA 2048 bit certificates will continue to work and no changes are needed to them.
Certificates requested with ECC (elliptic curve) keys are unaffected and Sectigo will still sign certificates with keys using the NIST P-256 and P-384 curves.
Source: Sectigo’s Knowledge Base