It is possible for multiple visits to occur at the same time, for either a client or a carer. For this to happen, overlapping needs to be allowed in the settings for both visits. If it is not enabled for both, the second booking will not create due to clashing.
This is useful for when a client has two visits happening at the same time but for different lengths of time. For example, a client could have meal prep at 12:00 for 15 minutes and also domestic care at 12:00 for 45 minutes. In this case you only need to enable the client overlapping option for both bookings.
To turn this on, create or access a scheduled visit and double click on it. At the bottom of the resulting menu, there will be a drop down box titled Overlapping. Inside you will see the two options for overlapping clients and carers. Click Overlap client.
When you create the second booking, you must turn on this same setting or it will not allow it to be created, citing a clash as the reason.
This function was added with a very specific purpose, for example two people requiring care in the same location that one carer could complete with one booking for both.
For this setting, you must enable <Overlap carers> in the same field as above and create 2 bookings for the same carer.
This is not recommended because it can cause severe scheduling clashes if not monitored properly.