How do I overheat with MCH?

[WindyGamer]

I'm a level 51 MCH. And my next job quest is 50. So, I should have learned the Heat Blast skill at 35, right?

Well my gauge - the top orange one, is full and blinking and no HEAT BLAST skill to use.
Is that what I'm looking for, or something else? The spell tips are a little light on content and the MCH guide - the official one - is really just the tool tips on a web page.

So, is this a bug? Did they not enable that skill for me since I was already 51 when the patch happened?

Or am I doing something wrong and need to light up something else to get a HEAT BLAST to work?

This seems like a lovely skill that will help fill my foes full of more holes, but I can't get it to work.

BTW, have you noticed that you can do Spread Shot all day long now? I assumed it would use some resource and would eventually run out, but Nooooooo.,.. Just keeps going all day. Look, I'm not complaining... There is enough to complain about [Gee after all that work to light up a turret, it either should blow the foe away, or last a little longer, but nope.. 10 sec or something and it's gone. Sigh.] and a lot of things they got right [ In general I like the MCH changes I've seen. ].

How about that Heat Blast thing? Anybody got a clue? Or should I report a bug?

[Reinhardt_Azureheim]

You'd do well to use you Lv30 ability Hypercharge. That is your Overheat buff enabler.

[WindyGamer]

Super. That does the trick. Then you can wail away with Heat Blast for a while.. Cool
Thanks.