I saw of Vapi's pricing page, that concurrency is limited to 10 concurrent calls and was wondering if that only applies to phone limes or also Web SDK calls we'll start with Vapi and if it is a hard limit or would allow for temporary spikes in usage? Anyone have experience with the Vapi Web/iOS SDK rate limits?

Vapi’s 10-call concurrency limit applies account-wide across both phone and Web/iOS SDK calls; it’s a hard cap (not burstable), though excess calls are queued, you’ll need to upgrade your plan or purchase additional concurrency units..