with double albums my filenames are changed. so the order of the songs is not correct anymore. first the 1st song of cd2 is played, then the 1st song of cd1 and so on.
that's what my filename looks like:
X00001-01-01 - Eric Clapton - Just One Night.mp3
X00001-01-02 - Eric Clapton - Just One Night.mp3
...
X00001-02-01 - Eric Clapton - Just One Night.mp3

i use an ipad 2017 ios 12.0.1
transfer via function "media servers" from windows-pc to apple ipad

please have a look on it
Thanks