Mind Flay: Insanity will sometimes cancel the last tick when queuing an action

[seanpeters86]

Game Version:
11.0.2 live Build 56313

Description:
When you are casting Mind Flay: Insanity and queueing an action mid-channel sometimes it will cancel the last tick of Mind Flay: Insanity causing you to lose a tick of damage and Insanity, or sometimes just one or the other. This does not appear to be consistent but does happen more often when you queue an action vs. just letting the cast finish naturally.

Details:
TBD

Logs, Images, Videos

https://www.warcraftlogs.com/reports/Jph1aZjwmAXYWd9B#fight=23&type=casts&source=63&pins=0%24Separate%24%23244F4B%24damage%240%240.0.0.Any%24226499467.0.0.Priest%24true%240.0.0.Any%24false%24391403%5E0%24Separate%24%23909049%24resources%240%24226499467.0.0.Priest%240.0.0.Any%24true%240.0.0.Any%24false%24391403%24113&ability=391403&view=events

Reproducible:
Sometimes

Howto:

1. Cast Mind Flay: Insanity
2. Queue an action directly after, since it is 1 GCD in duration this should not result in any missed ticks