The Architecture remains same as Release 2.0 , there are no addition with reference to the overall architecture of ELIOT. - SD-WAN / WAN Edge / uCPE Gateway Blueprint. In Release 3.0 there are some new features added for ELIOT Portal Component , Quality Improvements and Bug fixing.
Refer the below link for overall architecture.
ELIOT Release 2 - SD-WAN / WAN Edge / uCPE Architecture Document