I have many Mikrotik devices: RB3011UiAS, RB4011iGS+5HacQ2HnD, RB750UPr2, RB952Ui-5ac2nD, RB941-2nD, RBcAPGi-5acD2nD
All were upgraded to 7.1.1 Stable.
All devices synchronized successful, and only one RB750UPr2 has such error - status is waiting.
Probably this is a bug.