The first freeze will occur before the start of the 1st Test between Eng-SL.(Feb 22)
Captains, will be able to make changes to their existing/create new team after the conclusion of the 1st test between AU-IND.(Feb 27-Mar 3) This period is called the Trading Period.
The 1st Trading Period will be open until the start of the 2nd Test between Eng-SL.(March 7th)
The 2nd Trading Period will only open after the conclusuion of the 3rd AU-Ind test(March 18-22) and will close before the start of the 3rd NZ-Pak test.(March 27th)
