An enbloc process is never straightforward. Sometimes an appeal may be lodged with the STB by aggrieved owners who felt shortchanged. Such appeals can take between six months to a year or more.
Going forward, you may want to sign one year leases with your tenant. You may like to know that the rules had been revised such that the minimum tenure for a tenancy is three months. This may be to your favour if your apartment is suitable.
There are usually clauses in Tenancy Agreement which specifically mention enbloc notification time frame. Check yours to verify if it was two or three months (norm).