Fixed by PR https://github.com/openshift/ansible-service-broker/pull/1051

BEFORE:
$ grep PUT multi-bind-bug.log  | grep service_bindings | grep ^172
172.17.0.1 - - [20/Aug/2018:20:18:32 +0000] "PUT /osb/v2/service_instances/0756dfff-a4b6-11e8-bc84-0242ac11000b/service_bindings/d45e60d7-abc3-4d19-9df0-d01358e08ff3?accepts_incomplete=true HTTP/1.1" 202 58
172.17.0.1 - - [20/Aug/2018:20:18:32 +0000] "PUT /osb/v2/service_instances/0756dfff-a4b6-11e8-bc84-0242ac11000b/service_bindings/d45e60d7-abc3-4d19-9df0-d01358e08ff3?accepts_incomplete=true HTTP/1.1" 400 45


AFTER FIX:
172.17.0.1 - - [20/Aug/2018:21:09:19 +0000] "PUT /osb/v2/service_instances/b7a26c99-a4bc-11e8-803d-0242ac11000a/service_bindings/75fae3ec-5ffd-4ff9-84fc-7702f1e48855?accepts_incomplete=true HTTP/1.1" 202 58
172.17.0.1 - - [20/Aug/2018:21:09:19 +0000] "PUT /osb/v2/service_instances/b7a26c99-a4bc-11e8-803d-0242ac11000a/service_bindings/75fae3ec-5ffd-4ff9-84fc-7702f1e48855?accepts_incomplete=true HTTP/1.1" 200 233
172.17.0.1 - - [20/Aug/2018:21:09:27 +0000] "PUT /osb/v2/service_instances/b7a26c99-a4bc-11e8-803d-0242ac11000a/service_bindings/e099efdf-7ddc-4f87-bc4d-bfbe12909e92?accepts_incomplete=true HTTP/1.1" 202 58
172.17.0.1 - - [20/Aug/2018:21:09:28 +0000] "PUT /osb/v2/service_instances/b7a26c99-a4bc-11e8-803d-0242ac11000a/service_bindings/e099efdf-7ddc-4f87-bc4d-bfbe12909e92?accepts_incomplete=true HTTP/1.1" 200 233
172.17.0.1 - - [20/Aug/2018:21:09:29 +0000] "PUT /osb/v2/service_instances/b7a26c99-a4bc-11e8-803d-0242ac11000a/service_bindings/7695f659-cae9-4c38-bf04-cd9d086e2a2f?accepts_incomplete=true HTTP/1.1" 202 58
172.17.0.1 - - [20/Aug/2018:21:09:30 +0000] "PUT /osb/v2/service_instances/b7a26c99-a4bc-11e8-803d-0242ac11000a/service_bindings/7695f659-cae9-4c38-bf04-cd9d086e2a2f?accepts_incomplete=true HTTP/1.1" 200 233
172.17.0.1 - - [20/Aug/2018:21:09:31 +0000] "PUT /osb/v2/service_instances/b7a26c99-a4bc-11e8-803d-0242ac11000a/service_bindings/1ebd7771-2ce3-43f8-9d79-7517e7eb6540?accepts_incomplete=true HTTP/1.1" 202 58
172.17.0.1 - - [20/Aug/2018:21:09:33 +0000] "PUT /osb/v2/service_instances/b7a26c99-a4bc-11e8-803d-0242ac11000a/service_bindings/1ebd7771-2ce3-43f8-9d79-7517e7eb6540?accepts_incomplete=true HTTP/1.1" 200 233

Recently added to advisory:
openshift-enterprise-asb-container-v3.11.0-0.20.0.0
openshift-enterprise-apb-tools-container-v3.11.0-0.20.0.0

Verified and Passed. 
v3.11.0-0.22.0
asbd: 1.3.12

$ . ./manybinds.sh 
!!!Loop 1
05af565d-f8b4-4363-8f58-86826b0eba95
binding ID: 05af565d-f8b4-4363-8f58-86826b0eba95
HTTP/1.1 202 Accepted
Content-Type: application/json
Date: Mon, 27 Aug 2018 06:35:47 GMT
Content-Length: 58
Set-Cookie: 89a6d633054ded194d4e1360cdc1fbef=cebb52fdb7c612d0554f6fefa24726c4; path=/; HttpOnly; Secure

{
  "operation": "348d904b-564a-4852-b01f-c51a212ab511"
}
!!!Loop 2
05af565d-f8b4-4363-8f58-86826b0eba95
binding ID: 05af565d-f8b4-4363-8f58-86826b0eba95
HTTP/1.1 200 OK
Content-Type: application/json
Date: Mon, 27 Aug 2018 06:35:49 GMT
Content-Length: 229
Set-Cookie: 89a6d633054ded194d4e1360cdc1fbef=cebb52fdb7c612d0554f6fefa24726c4; path=/; HttpOnly; Secure

{
  "credentials": {
    "DB_ADMIN_PASSWORD": "wDf5SsIHg4XY30LCCytw",
    "DB_HOST": "postgresql",
    "DB_NAME": "admin",
    "DB_PASSWORD": "test",
    "DB_PORT": "5432",
    "DB_TYPE": "postgres",
    "DB_USER": "admin"
  }
}

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHBA-2018:2652