Hi Dave,
We have two product lines: Charts and FMS Data. Maybe you are referring to FMS Data?
Addons for P3Dv4 and P3Dv5 are supported for AIRAC updates via FMS Data Manager and Manually at FMS Data .
These are for the addons and do not update P3D itself as per FAQ - Navigraph updates for FS9, FSX and P3D - #2
For which addons are you trying to update navdata?
Cheers
Ian