When placing lava/water and then exiting to menu, and then opening your world again the lava/water have stopped spreading. (The lava/water has freezed) It does not continue spreading when updated.
Linked issues
duplicates 1
is duplicated by 3
Comments 3
Dupe of MCPE-6694
Tommaso fixed it:
https://twitter.com/_tomcc/status/566210161229197312
Can confirm this on my iDevices.