1.3.19 and 1.3.20 are emergency bug fixes. Sorry for the trouble.
You can extend the duration and/or extend the volume by purchasing another subscription within MyTrails.
When you purchase another subscription, if it is the same “size” as a current subscription, it by default extends the duration, but you can select the option to add to the current subscription area instead.
Purchasing a subscription of a different size always adds to the area rather than extend the time.
MyTrails lets you freely define the locations you download offline, so you don’t have to select a particular map number or administrative division when you purchase a map. Also, when you no longer need to have a given map offline, you can remove it and download another map without any additional cost (like a map lending library), so you don’t have to pay for a very big subscription, only what you need to have access to simultaneously.
This flexibility does mean that we can’t offer perpetual licenses (similar to owning, but in the digital world actual ownership is getting scarce).