If your agreement contains some vesting period or vesting date, they will get their stake in equity on said date or period and on conditions prescribed in the agreement but if there are no specific vesting terms then they will get their equity share on grant date which is the date on which share in equity was granted. If you are looking for an answer to how your stakeholders will be compensated on exit then the answer is that they will be compensated on the maturity of deal as per the percentage of equity they hold in business.