If you wish to transfer the domain name to the buyer who wants the domain to be transferred to another registrar then the mandatory lock in period of 60 days has to be followed.
But if one ask the buyer to select the same registrar with whom the domain is currently locked then after the buyer create an account the domain can be pushed to the buyers account since the now domain registrar is same. In domain pushing the receiver gets registration for the domain only for the remaining days until the next renewal and it is an instantaneous process.