The current AMR Balance Druid rotation has a comment about not using Convoke during CA because “It is best not to use this during Celestial Alignment or Incarnation”. This goes against usual advice, so I went and tested it out and I couldn’t reproduce the results that would lead to that conclusion.
Note: all results here are using my patched version fixing Starlord/Eclipse bugs with Convoke, see Balance Druid + Night Fae "Convoke the Spirits" bugs
Comparison here: https://www.askmrrobot.com/wow/simulator/report/7e22e6e99e2d4b7fb8e6a5d2e46f4435 – you can see that using Convoke during CA is a good 2-3 %pt improvement, well outside of stddev. This is using (HasBuff(CelestialAlignment) or CooldownSecRemaining(CelestialAlignment) > 15)
as the condition for Convoke – basically, trying to keep alignment as much as possible (at T+0, T+360), but not delaying for long enough to miss casts in practice.