pglogical replication dies

Hi,
I tried to setup upgrade using pglogical - from 9.5 to 11.

I did set it up, and after subscription, initial data sync seems to work
fine, but then replication dies.

In logs on subscriber, every 3 minutes I see:

db=,user= LOG: background worker "pglogical apply 114610049:2875150205" (PID 28020) exited with exit code 1

On provider there are more messages. Every 3 minutes I get:

LOG: replication connection authorized: user=some_user SSL enabled (protocol=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384, compression=off)
LOG: starting logical decoding for slot "pgl_somedb_provider_subscription"
DETAIL: streaming transactions committing after 4AA0/5B43630, reading WAL from 4AA0/55743C0
LOG: logical decoding found consistent point at 4AA0/55743C0
DETAIL: There are no running transactions.
LOG: could not receive data from client: Connection reset by peer
LOG: unexpected EOF on standby connection

And that's all.

If it matters there are ~ 3000 tables in the replication set, and we
don't replicate sequences (figured it will be simpler to just sync them
once on switch to new server).

How to debug/diagnose the problem?

Best regards,

depesz