Claudio always on time through two days and one more (10)

I haven't cracked this one yet — but the brilliant team at Fifteensquared have:

definition: Claudio Monteverdi the composer [wiki] EVER="always" after/"on" T (time) both going into/"through": MON (Monday) and D (day) i.e. "two days"; then I="one" added/"more"