diff --git a/README.md b/README.md
index 0af97e1..e58c7a7 100644
--- a/README.md
+++ b/README.md
@@ -20,12 +20,21 @@ mailboxes:
 - `ano@produktor.io`
 - `postmaster@produktor.io`
 - `postman@produktor.io`
-- `wheregroup@produktor.io` — incubator mailbox (issue #251): nobody logs in;
-  legacy `.eml` corpus is imported via `doveadm import` by the ETL connector.
+- `andriy.oblivantsev@wheregroup.com` — incubator mailbox of the гдеgroup
+  period (issue #252): the owner's **historical address**, not an abstract
+  source box. Nobody logs in; legacy `.eml` corpus is imported via doveadm by
+  the ETL connector (`bin/mail/incubator.go`, 2dph), routed to
+  `Sent`/`INBOX`/`INBOX/Unmatched` by the recipient headers.
+- `wheregroup@produktor.io` — superseded A1 pilot box (abstract "source"
+  model, issue #251): its 1000 imported messages are migrated to
+  `andriy.oblivantsev@wheregroup.com` and the account is then deleted (issue
+  #252). Listed until deletion; `user-patches.sh` skips owners that are no
+  longer in `postfix-accounts.cf`.
 
 Passwords live in `.env` (`INFO_PASSWORD`, `ANDRIY_PASSWORD`; `ano@` uses
-`GATOR_MAIL_PASS` in the gator repo `.env`; `wheregroup@` uses
-`WHEGROUP_PASSWORD`, random — no interactive login). Do not commit `.env`.
+`GATOR_MAIL_PASS` in the gator repo `.env`; `andriy.oblivantsev@wheregroup.com`
+uses `ANDRIY_WG_PASSWORD`, random — no interactive login; `wheregroup@` uses
+`WHEGROUP_PASSWORD`). Do not commit `.env`.
 
 ## Web UI (Roundcube)
 
@@ -75,21 +84,24 @@ changedetector (`check-for-changes.sh`, polls every 2 s) picks up the edited
 Dovecot. No mail is lost, no container recreation.
 
 ```bash
-# 1. random password for the new source mailbox (stored in .env only)
+# 1. random password for the new historical-address mailbox (stored in .env only)
 PW=$(openssl rand -base64 24 | tr -dc 'A-Za-z0-9' | head -c 32)
-printf 'WHEGROUP_PASSWORD=%s\n' "$PW" >> .env            # never commit .env
+printf 'ANDRIY_WG_PASSWORD=%s\n' "$PW" >> .env        # never commit .env
 
-# 2. add the account — password is read from stdin, never from argv/ps
+# 2. add the account — password is read from stdin, never from argv/ps.
+#    DMS accepts any virtual user: the domain need not be serviced by
+#    mail.produktor.io (verified live with wheregroup.com, issue #252) — the
+#    account only serves IMAP/doveadm, no inbound delivery.
 printf '%s\n%s\n' "$PW" "$PW" |
-  docker exec -i mailserver setup email add wheregroup@produktor.io
+  docker exec -i mailserver setup email add andriy.oblivantsev@wheregroup.com
 
 # 3. changedetector applies within ~5 s; verify
-docker exec mailserver doveadm user wheregroup@produktor.io
+docker exec mailserver doveadm user andriy.oblivantsev@wheregroup.com
 
 # 4. give the fresh mailbox an INBOX (a brand-new owner has none — without it
 #    `doveadm mailbox list -u <owner>` is empty and user-patches.sh cannot
 #    record any share), then apply the shared/ACL policy
-docker exec mailserver doveadm mailbox create -u wheregroup@produktor.io INBOX
+docker exec mailserver doveadm mailbox create -u andriy.oblivantsev@wheregroup.com INBOX
 docker exec mailserver /bin/bash /tmp/docker-mailserver/user-patches.sh
 ```
 
@@ -107,11 +119,13 @@ right sets for `info@`:
 
 - **production owners** (`ano@`, `andriy.oblivantsev@`, `postmaster@`):
   read-only — `lookup read` (issue #79);
-- **incubator owners** (`wheregroup@produktor.io`, later `gmail_lenovo@`,
-  `tb-*`/`pst-*`): read **and delete** — `lookup read delete expunge
-  write-deleted` (issue #251). The owner never logs in; mail arrives via
-  `doveadm import`. Deleting a message in Roundcube = filter/exclusion from
-  the corpus (auto-sync, epic B), so the delete button must work in `Shared/`.
+- **incubator owners** (one account per historical address of the owner:
+  `andriy.oblivantsev@wheregroup.com` for the гдеgroup period; later
+  `eslider@gmail.com`, `...@viscreation.de`, ...): read **and delete** —
+  `lookup read delete expunge write-deleted` (issue #251). The owner never
+  logs in; mail arrives via `doveadm import`. Deleting a message in
+  Roundcube = filter/exclusion from the corpus (auto-sync, epic B), so the
+  delete button must work in `Shared/`.
   Verified on live: `write-deleted` is sufficient for the `\Deleted` flag
   Roundcube sets (no extra `write` right needed), `expunge` is also what
   Dovecot MOVE needs on the source side when Roundcube moves a deleted message
diff --git a/config/user-patches.sh b/config/user-patches.sh
index ea32184..e91ea1a 100755
--- a/config/user-patches.sh
+++ b/config/user-patches.sh
@@ -3,11 +3,18 @@
 # two owner classes (issue #79, issue #251 / epic #250):
 #   - production owners (ano@, andriy.oblivantsev@, postmaster@): read-only
 #     (`lookup read`) — one login in Roundcube covers the whole account list;
-#   - incubator owners (wheregroup@produktor.io; future sources like
-#     gmail_lenovo@, tb-*/pst-*): read + delete (`lookup read delete expunge
+#   - incubator owners: read + delete (`lookup read delete expunge
 #     write-deleted`) — the mailbox owner never logs in, mail is imported via
 #     doveadm; deleting a message in Roundcube = filter/exclusion from the
 #     corpus (autosync, epic B).
+# Incubator model (corrected 2026-09-02, issue #252): the incubator mailbox IS
+# the owner's HISTORICAL ADDRESS per period, not an abstract "source" mailbox.
+# The wheregroup period = andriy.oblivantsev@wheregroup.com; later periods get
+# their own account (eslider@gmail.com, ...@viscreation.de, ...).
+# wheregroup@produktor.io stays listed as the superseded A1 pilot box until
+# its 1000 messages are migrated and the account is deleted — grant_share
+# skips owners that are not (yet) in postfix-accounts.cf, so a deleted account
+# is a silent no-op.
 # DMS runs this only on the FIRST start of each container instance (plain
 # `docker compose restart` skips the setup step by design — /CONTAINER_START
 # marker), so it must stay idempotent. ACLs, the shared dict and subscriptions
@@ -31,7 +38,7 @@ chmod 0770 "${SHARED_DB_DIR}"
 #    when Roundcube moves a deleted message to Trash.
 READER='info@produktor.io'
 PRODUCTION_OWNERS='ano@produktor.io andriy.oblivantsev@produktor.io postmaster@produktor.io'
-INCUBATOR_OWNERS='wheregroup@produktor.io'
+INCUBATOR_OWNERS='andriy.oblivantsev@wheregroup.com wheregroup@produktor.io'
 
 grant_share() { # $1=owner, remaining=right names
   local owner=$1