I have now published on GitHub the test version of the Aqara P1 Motion Sensor driver that worked for me after updating the FP300 firmware.
Driver version is "2.1.3", time stamp "2026/05/29 8:43 PM"
Note, that at this time the changes are only in the multi-device driver, not in the dedicated FP300-only one. If the patches are working with this driver, hopefully the dedicated driver will be updated as well.
Use the HE inbuilt 'Device' driver to delete the old states, attributes, child devices, etc.. when switching between the two Aqara drivers.
You will need to pair the FP300 one or two more times to your hub after switching to the P1 driver. If the initialization works, the 'motion' attribute should change automatically to active/inactive, without clicking on the Refresh button.