No special access issues
The base of the boulder is often partially submerged. When the water level (EH2000) is above 20 cm, then there is water on all sides of the boulder. With the water level below 10 cm, the southern side is dry. For the whole boulder to be dry the water level would need to be below -40 cm, which has happened but is very rare. It is possible to check the water level in Kunda here: https://www.ilmateenistus.ee/meri/vaatlusandmed/kunda/?lang=en
Alternatively, it is possible to climb in the winter when the sea is frozen or by dealing with the shallow water is some other way.