Dispatchers do not have an option to re-load Central Dispatch to view latest status of Tasks and Technicians.
Re-loading Central dispatch using browser refresh button resets user selection.
This is an expected behavior i.e, the search and the expanded user list will not be retained.
The reason why the number reduced is because when you navigated to next day, it will forget about you have tried to load all members and it will try to fetch the suggested agents for the new date.
This issue has been fixed in NewYork as a part of product enhancement.
Currently there is no work around to this issue.