The bug
In 1.16.2, Java Edition updated portal mechanics with two major new features:
The search radius is now proportional to the dimension scale factor, meaning portals will only search a range of 16 blocks in the nether, compared to 128 in the overworld
Portals use the POI system to cache links, meaning two portals that are linked will stay linked until one of the portals is destroyed
These changes were not ported to Bedrock Edition, meaning the confusing behavior described in MCPE-39609 still persists.
More information about this change can be found in MC-197538
Linked issues
is duplicated by 14
MCPE-151171
[Parity?] Overworld portals links to wrong Nether portals
Resolved
MCPE-151851
Nether portal does not return to original in overworld but creates new
Resolved
MCPE-154548
misbehaving nether portals
Resolved
MCPE-157464
Nether Portal leads to a different location in the Overworld when exiting the Nether
Resolved
MCPE-159900
Nether portals in Overworld all connect to same portal in Nether
Resolved
9 more links
relates to 1
Comments 3
This is also related to MCPE-47288, which highlights the missing portal mechanic that was recently fixed for Java at MC-67.
tryashtar
Affects 1.19.22
Relates to MCPE-154548