Since the connection instance tracks the last seen RUN's SUCCESS' tfirst, a subsequent run of the same transaction overwrites the tfirst of partially consumed results of a previous run.
Having each stream track their own tfirst avoids this problem.
Note: this only happens to Bolt4, since it is not possible to pull partial results with Bolt3 (only PULALL is available).
Since the connection instance tracks the last seen RUN's SUCCESS' tfirst, a subsequent run of the same transaction overwrites the tfirst of partially consumed results of a previous run.
Having each stream track their own tfirst avoids this problem.
Note: this only happens to Bolt4, since it is not possible to pull partial results with Bolt3 (only PULALL is available).