A little more digging on this problem (of no navdata updates for PDMG on Xbox) and potential solutions:
Navigraph offer navdata in the sim, with an “unlimited” subscription, on PC. This includes “Sim Updates” which allows you to substitute Navigraph data for Navblue, and “Addon Aircraft Updates” which are tailored updates for specific planes like the PMDG 737 which come from the marketplace with Navigraph data embedded.
“we have developed the Navigraph Hub, an innovative solution that enables you to replace and update the default MSFS navigation data with Jeppesen Navdata.”
Navigraph’s Stephen O’Connell on Discord: “We are working actively with PMDG on a solution for navdata updates on Xbox.”
But PMDG’s Mathijs Kok says by email yesterday, “It’s all in Microsoft’s hands”.
The PMDG forum thread on this issue dried up a few months back:
https://forum.pmdg.com/forum/main-forum/pmdg-737-for-msfs/251900-outdated-nav-database-on-xbox
This week PMDG teased a long-promised EFB tablet on their forum, with an announcement by Robert Randazzo to come this weekend - but will it include the ability to update navdata on xbox?
“RSR will fill you in with a feature list, more images, and a release date this weekend.” - Mathijs Kok, PMDG Simulations
https://forum.pmdg.com/forum/main-forum/general-discussion-news-and-announcements/267696-just-saying
I am able to enter my Simbrief credentials in to the 787 FMC to download flight plans from Simbrief / Navigraph on Xbox, so I see no reason why we can’t do the same for navdata updates.
I don’t mind paying for data, and I hope that Xbox, Microsoft, Navigraph, and PMDG care enough about this to work together on a solution. I recognize I am a minority user on Xbox, but my money is hard earned and just as green. If it’s not feasible to provide navdata updates on Xbox, then you must clearly say so in the Marketplace BEFORE purchase. Thanks.