MySQL 5.6 -> 5.5 replication is violated if 5.6 node uses gtid, binlog checksums or new ROW event formats. These can be prevented by configuring 5.6 node with:
log_bin_use_v1_row_events=1 gtid_mode=0 binlog_checksum=NONE
With this configuration, at least basic 5.6 -> 5.5 replication seems to work. But more testing is needed...
MySQL 5.6 -> 5.5 replication is violated if 5.6 node uses gtid, binlog checksums or new ROW event formats. These can be prevented by configuring 5.6 node with:
log_bin_ use_v1_ row_events= 1 checksum= NONE
gtid_mode=0
binlog_
With this configuration, at least basic 5.6 -> 5.5 replication seems to work. But more testing is needed...