Choose Signing Key for a Shared Access Signature

Hi, I use Terraform to generate 180 day Shared Access Signatures and would like to rotate the Storage Account Access Keys which are used to generate them. When I do that, any existing Shared Access Signatures will require regeneration (I assume immediately) So I want to alternate the signing key which is used to generate the SAS and rotate the unused Access Key before the next 180 day SAS is generated. I can’t seem to find a way with of choosing which access key to use when creating a new SAS.
Has anyone done this, or can anyone offer some guidance on how to approach this?
Thank you.