Navigating Payout Delays with Multiple PSPs for Cross-Border

We've been running into persistent friction with payout reliability, specifically on cross-border transactions using multiple Payment Service Providers. While the initial onboarding and KYB processes were arduous but ultimately completed, the real headache begins when funds clear one PSP but then take days, sometimes a full week, to become available via another. This isn't about the raw transfer time, but the internal reconciliation and release on their end.

It's creating a cash flow bottleneck for our operations. We've tried staggering payments, using different providers for different regions, but the variability is still too high. Has anyone found a robust way to manage multiple PSPs where the handoff between them for payout isn't a black box? I'm curious about the specific clauses or service level agreements others have negotiated, or if there's an industry standard for this I'm missing.