Disadvantages of tibicos mushroom to your health?

It’s a good sign in that it probably signals turnover to a healthier gut community but you don’t have to force the process.
When I first began drinking water kefir I drank only a tablespoon or so per day for several days. Even that small amount caused gut activity I could sense but there were no overt symptoms of distress. After that, I increased the daily amount gradually and by day 10 I could drink a full glass.
Once fully acclimated, I found it good to pay attention. If the first swallow tasted great, I drank as much as I wanted. If it didn’t–and some days it didn’t–I didn’t drink any more. There were some days I didn’t drink any, and other days I was very thirsty for it and it tasted great.
I think the amount we need/want varies in reaction to what else is going on in our diet and activities.

yes, its a side effect from die off. Any product that is fermented in some way will result in this effect if its too much for your system.
They suggest you cut back a bit til its tolerable (I believe also eating more carbs also helps).
This effect is different for everyone, depends what is going on in there. Just monitor it, tweak it, increase when you feel you can, cut back again if same result. If its disrupting your system its working, but there is no need to suffer, just slow it down and keep going.
it takes time to repopulate the good and get rid of the bad