This was seen live on a Twitch broadcast (not going to post link to remain anonymous, sorry).
Steps to (hopefully) reproduce:
ults Tryndamere 
Not a bug. He can even ult while suppressed
Also, Blitz's silence on ult only lasts 0.5 seconds, so it's not as if he's gunna die that quick.
Read the abilities in question before submitting bug reports, please.
If silence stopped Tryndamere's ult he'd be hilariously weak.
Tryndamere can ult while supressed and stunned...
This is intended, the tool tip for his ult reads that he can use it even while under the effects of CC.
