FYI only:
If one suspected that any Volvos SW has been changed from original, it would then also have a different PN and any dealers Vadis PC can easily identify any ECUs SW PN. The SW PN is not written on the outside of the ECU, the PC accesses it. One can also check boost with a guage so one can indeed verify IF anyone tampered with OEM specs, it's not rocket science.

Worst case senerio, IF you seriously overboost and blow the engine, Volvo will most likely research the matter to find out why it blew, not just simply replace the engine under warranty w/o questions. Volvo (VCNA, etc) also knows about the existance of all the aftermarket mods that can void warranty and they'd rather not pay for a costly replacement engine that blew, not Volvos fault. The engines also don't normally blow so it would be very suspicious.
Doubling the boost may not cause it blow BUT it is possible and you should be aware of that.