The maximum number of provisioning profiles and .p12 certificates you can upload to the Code Signing tab on Bitrise is 30.
If you have a large number of provisioning profiles and certificates, you can use Fastlane Match Step to manage these.
Learn how you can configure the Fastlane Match Step.
If you don't want to use the Fastlane Match Step, you can find tips on managing the number of profiles and certificates in our iOS code signing document. This way you can change the following Certificate and profile installer Step inputs for each white label app:
Provisioning profile URL
Please note that the Certificate URL and the Provisioning profile URL can be both an URL and a file path. This way you could zip up every cert/profile and extract into the VM and target them as you see fit.