Every other day is sort of just SOP on the North Beaches (CB/MR)

It's more of an allocation thing to slow down exploitation on the NON-treaty side. QIN get's its 50% share of the total clam harvest from those beaches. For years now, the state-managed digs will go alternate days between CB and MR thru a diggable series of tides, whereas TH to the south (with no treaty rights) will typically be open consecutive days for the entire series.

This strategy effectively slows the state's exploitation rate by ~50% across the entire North Beach. The only reason there weren't digs open at MR on the alternate days was because MR is still officially tainted with DA (as are TH and LB)