Hello Robert
The adj-RIB-In table will not be refreshed when using a soft reset. The table is static only in the sense that it will not change when implementing a soft reset. But this table isn’t static in general. If there are changes to routing that BGP neighbours send to the local router, these will go into the adj-RIB-In table and be updated.
A hard reset will repopulate the adj-RIB-In table, however, like Rene mentions, it is not preferred. If the router in question supports it, the most preferred method is the Dynamic Soft Reset option also known as Route Refresh. This will indeed refresh the table by requesting new information from the BGP neighbours however, this will occur without disruption. More about the Route Refresh option can be found in the following lesson:
I hope this has been helpful!
Laz