Question about Miracle Time.

It seems MSEA will be doing this on March 16th and 17th and I have some cash left to use, so I thought I'd get some info first.

When I look at the description from Nexon's website it says that cubes are more effective during this time but also that the chance of a potential tier upgrade is higher than usual. I've seen positive results of both kinds during these threads but they could have just been coincidental so I would like to know which of the two have you seen to be more likely as I have a legendary Witch Belt and an epic Spectrum along with a unique Carte Finale, all of which could use some work to be amazing.

Thanks for your input!

[COLOR="#0000FF"]what.
link plz ! or sources! [/COLOR]