Verify/RateLimits: Are mixed-property rate limits based off the combination of properties?

Question

I am attempting to use the Verify product's Rate Limit feature. I am confused about this piece of the documentation regarding mixed property rate limits:

The flexibility afforded by Rate Limits in Verify means that you can enforce limits on "mixed" properties simply by concatenating values together. This is particularly helpful for enforcing rate limits on properties that are highly correlated. Possible examples of highly correlated properties include: ...

• Phone Number and End User IP Address

In this example, if I use a rate limit on phone number and end user IP address, will the rate limit be applied when the max number of requests are made by the combination of (phone number, IP address), or when the max number of requests are made by either phone number OR IP address?

If it's the second, does this at all behave differently than if you were to just include multiple rate limits in your call to the create verification API, like below?:

client.verify.v2.services('VAXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX')
                .verifications
                .create({rateLimits: {
                   end_user_ip_address: '127.0.0.1',
                   phone_number: '+18188887777',
                 }, to: 'to', channel: 'channel'})

This is a documentation question