Some type of Bolete - bitter perhaps?

Some type of Bolete - bitter perhaps?

Observation - Some type of Bolete - bitter perhaps? - UK and Ireland. Description: Large groups of these fungi, approximately 10cm in diameter. The older specimens were starting to rise up around the edges showing the underside.

Large groups of these fungi, approximately 10cm in diameter. The older specimens were starting to rise up around the edges showing the underside.