My guess it is permanent, where NowTV have updated this linked help article below (either last night or this morning) and removed the Nat Geo Wild channel off the list and replaced it with National Geo only.
I did notice 6 number Wild Geo TV on demand shows at the bottom of the new Nat Geo channel in the entertainment folder though.
I also miss National Geographic Wild channel on Now TV!
There was no real warning that the Channel was being replaced by the main National Geographic. I believe there may have been an email sent last year but I wasn't subscribed to any Now TV package at the time so I didn't receive it.
The Channel was removed right in the middle of it showing the latest Snakes in the City series and I now cannot get this anywhere as I do not subscribe to Sky, Virgin or Talk Talk TV.
TV Player used to show Nat Geo Wild but have also removed this channel a little while ago so there really isn't anywhere else to receive it unless anyone else has any suggestions regarding this?