461. Persons who may enforce tenant's covenants.

An assignee of the reversion is entitled to sue in respect not only of rent due and breaches of covenant which occur after the assignment to him, but also in respect of rent due1, and breaches of covenant which have occurred prior to the assignment to him2. After an assignment of the reversion it is accordingly the assignee who alone may sue for rent and for breaches of covenant whenever they have occurred, at any rate unless the assignee and the assignor have agreed to the contrary