Why not to use Preview calling with blended ACD agents

It is not a good idea to run a Preview campaign with blended ACD agents. Here's why:

Preview Calls do not use ACD. Occasionally, customers use Preview Dialing with a blended ACD environment. There is no inherent restriction against this, but slight risk is involved. "Preview Dialing" is a non-ACD dialing mode. When preview dialing is used in a blended ACD environment, it is possible that an ACD interaction will be routed to agents while at the same time, a Preview call is assigned to an agent's queue. Once the agent is placed into a "Campaign Call" status, ACD server will not route additional ACD calls to that agent. However, that small window of time when the agent is available could be enough time to receive a Dialer and ACD interaction at the same time. For this reason, it is not advised to run a Preview calling mode campaign with blended ACD agents.