Bertinet "Dough" question

Hi all

Im just starting out and am amazed at all the ideas and spending endless amounts of time on this forum learning

A really basic question is that Im getting confused with yeast quantities

Ive got Bertinets Dough recipe book and he specified an amount of yeast to use (often 10g). Im assuming this is fresh yeast but he doesnt clarify that really

But then Ive read around that if you re not using fresh yeast, the quantity should be adjusted (I use instant yeast so 1/3 should be used instead?)

Ive found that I use instant yeast to the quantities Bertinet has listed for fresh yeast and sometimes my bread comes out with a slightly bitter taste? So Im assuming this is a problem with yeast quantity cos my house is cool and I dont allow it to proof to long.

So question really is... Do I need to adjust yeast quantities in Bertinets Dough as I am using instant rather than fresh!

Thanks all!