Enabling Pilot Assist and Adaptive Cruise Control

[IMAY2023]

Well, that's indeed strange. According to VOLVO accessory information, T8 and mild hybrids B series should not need to replace the unit. 
In any case there are many folks here who has enabled the  ACC and PA without changing the  238 TOP DAMPING, BRAKES  or replacing the unit. 
You can also check your part number and verify its variant to part catalog.