Suspicious SSL TPS Spikes

Hello,

I'm kind of struggling to wrap my head around some weird spikes I'm seeing on the F5 BIG-IP Dashboard.

We had two of these spikes this week, hitting like x1200 more SSL TPS than our usual high average.

I'm thinking it might be some kind of attack, given the fact that we also faced some DDoS recently, but honestly, I have no clue how to dig deeper into it. 

Or is it possible to be a bug (found this: https://cdn.f5.com/product/bugtracker/ID499348.html) ?

Any ideas are highly appreciated, thank you!