International cricket operates on a four-season cycle, which fits nicely into the twice-per-season international breaks in the World Series season. I still need to check that all of these series are completely accurate, because I do have a spreadsheet with them all on for just such an eventuality.
Season One
Phase One
Ireland Tour of Australia
New Zealand Tour of England
Zimbabwe Tour of Pakistan
India Tour of South Africa
Bangladesh Tour of Sri Lanka
Afghanistan Tour of West Indies
Intercontinental Cup Matches
Phase Two
New Zealand Tour of Afghanistan
Sri Lanka Tour of Australia
South Africa Tour of Bangladesh
England Tour of Ireland
Pakistan Tour of West Indies
India Tour of Zimbabwe
Intercontinental Cup Matches
Season Two
Phase One
Australia Tour of Afghanistan
England Tour of India
West Indies Tour of Ireland
South Africa Tour of New Zealand
Bangladesh Tour of Pakistan
Sri Lanka Tour of Zimbabwe
Intercontinental Cup Matches
Phase Two
Cricket World Cup
Season Three
Phase One
Bangladesh Tour of England
Afghanistan Tour of India
New Zealand Tour of Ireland
Australia Tour of Pakistan
West Indies Tour of Sri Lanka
Zimbabwe Tour of South Africa
Intercontinental Cup Matches
Phase Two
Ireland Tour of Afghanistan
England Tour of Australia
Zimbabwe Tour of Bangladesh
New Zealand Tour of Pakistan
South Africa Tour of Sri Lanka
India Tour of West Indies
Intercontinental Cup Matches
Season Four
Phase One
Pakistan Tour of England
Sri Lanka Tour of India
Bangladesh Tour of Ireland
West Indies Tour of New Zealand
Australia Tour of South Africa
Ireland Tour of Zimbabwe
Intercontinental Cup Matches
Phase Two
World Test Championship Final
Intercontinental Cup Promotion Playoffs