Anime Concerts during 16th - 30th April

Basically are there any anime concerts during the 16th - 30th of April.
Is there a link that shows me what is on and where?

No big one like アニサマ,アニマックス,リスアニ and more.
http://anisama.tv/
https://musix.animax.co.jp/

But smaller events are so so.
http://anime.eiga.com/event/cal/201704/
http://anime.pia.jp/list.html
ライブ(Live) is so.

What title (TV/Movie), voice actor/actress, anisonartist you like?
Checked each official web/twitter?

I don't really mind I was just hoping to find something similar to a mix mash of that year basically.
But I guess probably isn't possible.
Thanks though.

Super Robot Spirits movement is celebrating its 20th anniversary with two concerts on April 29-30 and lots of anime singers, but these will be mostly oldies from the 70s-80s. The first day will be heavily Gundam classics.

Thanks for the additional info.
A fan of Gundam. But not much of a fan of the classics.
If it was part of the more modern franchaise I would be game for it. (Seed, Iron Blood, Builders, 00 etc.
)