Alternative to switchback for network effects

What are some alternatives to switchbacks and cluster Neighborhood sampling to get around network effects?

For example, if you have a sales funnel that’s entire phone-based and you want to test an intervention and find out if it improves the probability of conversion. If a switchback was run, and if the variant causes a huge volume of phone leads, then it could impact the control even days later if the backlog of leads to call is large enough