@whiteman,

It depends on how many maps you have downloaded.
How fast the SD card is.
Having a high end card is the best for speed.
How fast the Tablet is.
How many other apps are running in the background
How much space you have left on the SD or memory.

On my P8 lite smartphone it takes seconds for it to load with Android 6.
32GB SD Card
Germany, Belgium, Holland and Luxembourg

On my P20 lite even faster with the same maps with Android 8
64GB SD Card