When a subnet is created without any particular specifications, first allocated IP is the second IP of the subnet (the first is use for the gateway by default). But the latter allocated IP could be set from the last IP of the subnet. It should continue to use IP from the start of the subnet and re-use freed IPs.
+--------------------------------------+------------+--------+------------+-------------+--------------------------------------------------+
| ID | Name | Status | Task State | Power State | Networks |
+--------------------------------------+------------+--------+------------+-------------+--------------------------------------------------+
| dd6ff75c-8424-471b-bc3b-260545c65075 | compute1 | ACTIVE | - | Running | private=10.0.0.3; overlay=10.0.1.3 |
| 15e13606-b570-42a1-ba5e-38bdd803a61d | controller | ACTIVE | - | Running | private=10.0.0.2; overlay=10.0.1.2 |
| 3d5ed19a-8e95-4372-ba21-f8b97bceb726 | test | ACTIVE | - | Running | private=10.0.0.254 |
| cd2dc5a7-e472-415a-9dc8-cbc6d99f8d67 | test1 | ACTIVE | - | Running | private=10.0.0.253 |
| 021fa26e-b9c9-4b8e-b8b5-ce406d8458b5 | test10 | ACTIVE | - | Running | private=10.0.0.244 |
| 8a7f865b-26c4-4149-9a08-1437190814a4 | test2 | ACTIVE | - | Running | private=10.0.0.252 |
| 61d78b5f-3512-4ca6-ae3d-2cb688e489c3 | test3 | ACTIVE | - | Running | private=10.0.0.251 |
| 6db1b647-b950-4f1d-a4a4-c0284aae9ad9 | test4 | ACTIVE | - | Running | private=10.0.0.250 |
| 3a51bc22-dfe1-4c24-a647-6c89856ff73b | test5 | ACTIVE | - | Running | private=10.0.0.249 |
| b6f4f629-eaef-4154-b81d-12c9ea715f3a | test6 | ACTIVE | - | Running | private=10.0.0.248 |
| 2a7c4765-c172-4c95-a304-af4979898117 | test7 | ACTIVE | - | Running | private=10.0.0.247 |
| 7d3a8fb8-33d1-426a-b0d7-d9b3da04ea83 | test8 | ACTIVE | - | Running | private=10.0.0.246 |
| 15b02451-44dd-4586-8017-4cab37fc2629 | test9 | ACTIVE | - | Running | private=10.0.0.245 |
+--------------------------------------+------------+--------+------------+-------------+--------------------------------------------------+
Atul you have any update on this.