There is some comment from time to time where users complain about lost savegames after updating to a new version.
Be sure, that this is not triggered by the game - the game is fully backwards compatible!
I do not know exactly why android decides to delete savegame data (if that is happening) but I believe it is, that ome devices will REMOVE the app before installing the new update.
Because of Design patterns, if the app is removed, the savegames get deleted (by android) automatically - I cannot do anything about it.
Unfortunately people does only complain in the (play market) comments, where I cannot react on it in any way, so I cannot help them.
If you have any problem, send me a mail and I'll try to help you - if you do not send a mail, then sorry, you are alone because I am simply not able to help you in any way - but I promise I will practice my precognition skill at least one day in the week :-)