When the light is switching from day (at sunset) to night, or in the morning when sun is rising, the light emitted from lava will briefly disappear for 2-3 seconds then reappear.
This is very obvious if the room's only light source is lava. Torch light was not affected and the light of torches does not disappear when the lava block next to it does.
Linked issues
Comments 2
Correct, it is the same issue reported in MCPE-136109. If you have any additional information you'd like to add to this issue, please head over there.
This could be the same issue that is reported in MCPE-136109.