AR2645 (right side of animation) plus large prominence (left side). AR 2645 flared at class C shortly after 12:00UTC, unfortunately whilst the camera was not capturing for the first part of this, but the tail end of the flare is captured as can be seen when the AR jumps in brightness about 2/3rds of the way through the animation.
Scope: Lunt LS60THa/B1200CPT, 2x Barlow
Camera: ZWO ASI174MM, FireCapture
Mount: Sky-Watcher NEQ6, EQMod
Processing: AutoStakkert! 2, PixInsight 1.8, best 10% of APs, 25% of 1,000 frames, 143 frames, 30s intervals.
Date: 6th April 2017, 10:23 – 12:42UTC (Break of 21 mins 11:53 – 12:14 UTC)
Excellent captures, pity that you missed the start of that C class flare!