I am considering using Twilio to provide a SaaS to multiple end-users. I believe that by using Twilio's sub-accounts, I can assign tenants to each end-user. I understand that the number of sub-accounts that can be created per Twilio account is 1000. This number is insufficient for my business, so I am considering creating multiple Twilio accounts and creating sub-accounts under them. If you are aware of any services that could serve as a reference for the implementation mentioned above, I would appreciate it if you could share and inform me about them.
I apologize for asking so many questions. I would like to know if there are any hard limits or rate limitations that might become bottlenecks when providing a SaaS. I am interested in architectural solutions and whether it is possible to lift these limits.