We have published Krill 0.15.1, which fixes a bug that causes CAs not to clear certification requests with their parents when they receive a new certificate.
This causes the CA to re-request a new certificate every time it contacts the parent which by default happens once a day. Another consequence is that this blocks key rolls from progressing.
We strongly encourage users of Krill 0.15.0 to upgrade at their earliest convenience.
https://community.nlnetlabs.nl/t/krill-0-15-1-contains-adult-language-released/64/1