BUG #18636: I am seeing a difference in behavior between 13.12 and 15.6 for full text searching

The following bug has been logged on the website:

Bug reference: 18636
Logged by: Glenn Cipolla
Email address: glenncipolla(at)gmail(dot)com
PostgreSQL version: 13.12
Operating system: Ubuntu 11.4
Description:

The following query

select to_tsvector('simple','RG147SW RG14 Greenham Road Newbury West
Berkshire')
@@ to_tsquery('simple', 'gree,west:*');

Returns false in PG 15.6, but returns true in pg 13.12. In 15.6 the code
returns 'gree:* <-> 'west':*.
In 13.12 it returns 'gree:* & 'west':*

This article says the 13.12 behavior was a bug that was fixed in 14.x
(https://akorotkov.github.io/blog/2021/05/22/pg-14-query-parsing/)

I have a dev team about to change their code to handle the new <->. Before
they do that, I would like a confirmation that this functionality is
1. A bug
2. The new functionality will not change back in newer versions. Do you
intent to stick with the <-> return value?

Thanks,
Glenn