Description of problem:
/etc/ppp/ipv6-up.local is not triggering when IPv6 address is present on PPP interface. Contrary to behaviour in CentOS 7. Manually running the script results in expected behaviour. I've checked that the script is executable, permissions appropriate etc. ip-up.local IS triggering so could be an oversight somewhere?

Version-Release number of selected component (if applicable):
pppd v2.4.7

How reproducible:
100%

Steps to Reproduce:
1. Create /etc/ppp/ipv6-up.local make it executable. Suggest creating a bash script which just echo something >> a file as a good test to see if its triggering.
2. Connect pppd to an endpoint which provides IPv6
3. ipv6-up.local is not triggered

Actual results:
ipv6-up.local does not appear to trigger

Expected results:
ipv6-up.local script should trigger automatically when IPv6 connectivity is available via the PPP that just came up.

Additional info:
My company builds bespoke PC based routers which use CentOS 7 PPP and in some cases multiple connection paths. Historically I used a helper script to ensure PPP and relevant services were alive triggered from ip-up.local and a cronjob. Things became more complex with IPv6 and multiple connection paths so I ditched the CentOS provided scripts entirely and created various scripts triggering via cronjon, ip-up.local and ipv6-up.local. This all worked very reliably on CentOS 7 and I am now trying to migrate this to CentOS 8 Stream. Most of the scripts worked as is with some minor tweaks however I am running into some unexpected behaviour...