Hi user_287327599, we are also developing similar solution on the same chips and have the same issue.
In the end, we started from the available development boards for BCM20730https://www.aliexpress.com/item/Free-shipping-1pcs-BCM20730-bluetooth-keyboard-module-bluetooth-remote-control-module/2020810520.htmland then going to port the firmware into the new BCM20735 chips as soon as find development boards for them.
Lets keep in touch!
Please, let me know if you have already found development boards for BCM20735.
BCM20735 is produced by Cypress and is already released (I received a few BCM20735PKML1G chips in the end of September), but there are still neither developments kits nor SDK available on the official page.
Can you please point out any concrete contacts where I can ask about the development support?
This question is partially answered here: https://community.cypress.com/message/29061?et=watches.email.thread#29061
If you are aware what exactly "tier 1 customers" have the support, can you please list them?