I've put a video of this occurring on Youtube (because the video file is too big to upload here!)
Briefly though, when you have a water column with soul sand at the bottom and you use dispensers with buckets to suck the water blocks back in, the bubble effect remains in the air (and continues to function as before).
Before triggering dispensers:
[media]And after:
[media]Resulting in a column of rogue bubbles:
[media]
Thank you for your report!
We're actually already tracking this issue at MCPE-56462, so I will resolve and link this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
If you haven't already, you might like to make use of the search feature to see if the issue has already been mentioned.
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