DMVPN - spoke redundancy
When deploying DMVPN, there are various ways of employing redundancy including DMVPN dual hub dual cloud as well as DMVPN dual hub single cloud. However, you can also apply redundancy at the spoke by providing connectivity via two or more ISPs.
Indeed, the use of redundancy at the spoke using multiple ISPs has become common practice, where one ISP is used as the primarily connection, and the other acts as a backup. One way to do this is to use VRF-Lite to segregate the routing table when a spoke has dual ISPs. With VRF-Lite, multiple VPN routing instances can be supported on the DMVPN spoke.
Links:
https://forum.networklessons.com/t/introduction-to-dmvpn/1300/73?u=lagapides