attach partition to parent table with default partition accessexclusive

Hi ,

We have a table    wbxdata (xxxx…)  partition by range(starttime) , and have a default partition, now we want to add a new partition and move the data from default partition to new added partition.

Begin;

  Alter table only  wbxdata … detach partition  wbxdata_pdefault;          ---from here, accessexclusive lock on wbxdata_pdefault default partition, and it block all query on parent table wbxdata.

 Insert into wbxdata_p2305 select * from wbxdata_pdefault where starttime >= ‘2023-05-01 00:00:00’::date and starttime < ‘2023-06-01 00:00:00’;

Delete from wbxdata_pdefault where starttime >= ‘2023-05-01 00:00:00’::date and starttime < ‘2023-06-01 00:00:00’;

Alter table only wbxdata attach partition wbxdata_p2305 for values from ‘‘2023-05-01 00:00:00’ TO  ‘2023-06-01 00:00:00’;

Alter table attach default partition;

End;

Is it expected to see all query even select on  parent table  wbxdata got blocked , when  detach default partition and attach default partition ?    Postgresql 14.7 version.

Thanks,

James