Currently the API has L1 contribution budget for the aggregate reports per source. This means that you cannot control how the budget is distributed across multiple buckets. The bucket can be the SDKs used to report the triggers or any category defined by the filters in aggregatable_values.

E.g. if one SDK (for example Firebase) is used to report a conversion as biddable, yet another third party SDK using that same conversion as non-biddable. We cannot control which SDK ends up registering and redirecting to us first. This race condition may cause one SDK to consume all the L1 budget and leave the other SDK with no budget.