On snapshot 20w19a, the Nether generation changed once again. That's normal. But I noticed that Fortresses and Bastions generated in worlds created before 20w19a cannot be located when using the /locate command.
(Note: I just discovered that this bug also affect Overworld and End structures, not only Nether ones). (I'm putting the most explained case, the Fortresses & Bastions, but for the other structures they also need a fix).
The seed is: 8825242716498603998. Today, on the new coordinates, there are a big Soul Sand Valley and a big Basalt Deltas, where on old snapshots were Nether Wastes, Crimsom Forest, and a Basalt Deltas.
Also, on Bastions, Piglins don't generate correctly, and even spawn there Zombified Piglins. Extra: On 20w21a this was overlaped with a lowercase error, but on 20w22a now this bug returned exactly as it was before 20w21a.
How to reproduce:
1) Use seed 8825242716498603998 on 20w18a/20w17a (versions for the example).
2) At spawnpoint, create a Nether Portal. There should be a Crimsom Forest with a Fortress.
3) Modify the structure.
4) For the Bastions, just go to the coordinates of the photos. (This also applies for the Fortress).
5) Finally, charge the world on 20w21a/20w20b-a/20w19a.
Note: The same bug applies for every version that changed nether generation. Examples are opening a world of 20w06a on 20w15a or opening a 20w15a world on 20w17a.
PD: If you see some spanish parts, that's because I use spanish, but now I'm reporting a bug. Thanks for hearing.
Notes: 20w19a trigger the advancements.
20w20a-b trigger the advancements.
20w21a don't trigger the advancements.
20w22a trigger the advancements again.