Add migrations for Drupal 7 ECK to Drupal 8/9

When I run `drush migrate:upgrage --configure-only`, the migrations for entities (`d7_eck`) are not created. Is it expected, should they be created manually? (The migration for the entity types and bundles are created as expected.)

Just echoing the above from @Alex. Migrating from Drupal 7 to 9, it seems that the types and bundle configurations migrate correctly but the actual entities themselves are not having migrations generated.

If I understand correctly, there should be the following migrations:
upgrade_d7_eck_type
upgrade_d7_eck_bundle

then there should be a migration per bundle (for all of the actual entities themselves.)

I think that these further migrations are the derived, follow up migrations but it does not look like they are being generated.

I'm wondering if I'm missing a step somewhere? Can anyone shed any light?

@emileacroweb I have found that all Follow-up migrations are skipped by \Drupal\migrate_drupal\MigrationConfigurationTrait::getMigrations() which is used to build a list of migrations to generate. I have commented out the check in in to generate the ECK (and other follow-up) migrations.