Delay in Meeting Joining with Zoom Meeting SDK

We are currently facing a significant delay when using the Zoom Meeting SDK in our react native mobile application. When more than 150 users attempt to join a meeting simultaneously, the joining process takes over 10 minutes, which severely impacts the user experience. I enrolled for 300 users plan.

Could you please provide insights into the following:

Are there any known limitations or restrictions when handling a large number of simultaneous join requests?
Are there any recommended optimisations or best practices to improve the meeting joining speed?
Would upgrading to a different plan or making configuration changes help resolve this issue?
Your prompt assistance would be greatly appreciated.