Max Transit Health Check Function

I have a Max transit (i.e. not a Duo). Since the Max Transit has only one radio what does Health Check do if it fails and I have either SIM A or SIM B selected? Does Health check function differently if I select Both SIMs in the SIM Card Selection?

It is as you expect, with both SIMs enabled a health check failure will cause a active SIM swap and the device will try and connect on the alternate SIM.