so Garmin did stop using .img for marine chart.
They use a gma at the root with a folder name Charts that containt 2 folders Tiles and a RDPs. In the RDPs got the id of the map and a .SRPD file.
Did i miss a big release note ? Anybody got more info.
thanks

Where is this written? Please provide a link to the studio.
No chartplotter user has ever heard of such a thing. They still use water maps the same way they always have.
Official (or clones) with .gma and .unl files, and without them (cracked).