When using ConnectALL to synchronize timesheets, unsynchronized Clarity entries can be overwritten.
There are two factors at play in this scenario.
The first factor is conflict management. Depending on which system is configured to win a conflict, if this were an ordinary field, one would expect contents to be overwritten by the higher priority system/last system to be updated. In a similar fashion, ConnectALL is having to decide who has the "correct" data here and the source system is winning and passing its available entries along to Clarity, thereby overwriting the field.
The second factor is the data structure of timesheet entries in Clarity. Some systems will store multiple time records and sum the hours to produce a total, however in Clarity, each time entry is a static value tied to the date of the entry. Therefore, any changes to the record affect the entire day and it is possible to overwrite the previous value entirely.
Because of how different systems handle their time entry storage, ConnectALL recommends unidirectional synching and using a single system as the source for time entry instead of trying to manage time in two different locations. See Work Log/TimeSheet Support for further information.