The problem is that if a recovered supplier accepts direct updates before being in sync, replica to that supplier and from that supplier is broken.

Use case in MMR with two suppliers M1/rid1 and M2/rid2

ldif RUV is : [ rid1_t0, rid2_t1]

T20:
M1 RUV is [rid1_t5, rid2_t6]
M2 RUV is [rid1_t5, rid2_t6]

M1 is recovered from the ldif file

T21:
M1 RUV is [rid1_t0, rid2_t1]
M2 RUV is [rid1_t5, rid2_t6]

T22:
ldapclient send update to M1
M1 RUV is [rid1_t22, rid2_t1]
M2 RUV is [rid1_t5, rid2_t6]

T23
M2 starts a replication session to M1, It will update M2 with updates [rid2_t1..rid2_t6]
M1 RUV is [rid1_t22, rid2_t6]
M2 RUV is [rid1_t5, rid2_t6]

But here replication is broken both ways. M2 does not know rid1_t22 in its CL and can not update M1. After the import, M1 CL has been cleared, so M1 does not know rid1_t5 and can not update M2.

This problem exist with ldif recovery but I think it also exists with backup recovery.