CMAP charts not updating
You occasionally get reminded that your CMAP chart is not up to date.

It is a good idea to update, and easy to do via the CMAP store accessed from within Expedition.
What is not so clear, once you have purchased your update, is that you must delete the obsolete chart from your device and download the updated version.
If you do not do this, then you will continue to use the obsolete chart loaded on your computer despite updating.
To purchase the update and remove the obsolete chart chart, go to C-Map:

Select Store, then YOUR ACCOUNT. Select the chart(s) to update and complete the transaction.
Once complete, exit the store and from Expedition select C-Map again and select My Maps. Within ON THE DEVICE, click the small triangle to the left of the relevant chart(s) then click remove.

Close the browser and restart Expedition. Go back to C-Map > My Maps, and select the updated chart(s) and download.