For newer submissions a fingerprint lookup does no longer provide MusicBrainz re…lease details, but only returns the recording ID. E.g. one request for a more recent AcoustID submission returns only:
> {'results': [{'id': 'dc7c8041-9748-4ccb-9bb6-8dd7618e91cd', 'recordings': [{'id': '1f3ea44d-598b-43c4-991d-b3eb0858ce45', 'sources': 8}], 'score': 0.942181}], 'status': 'ok'}
A submission from last year returns more details:
> {'results': [{'id': 'f340943d-0330-477e-be7a-2415b44bcb67', 'recordings': [{'id': '0a138767-3d98-42c7-957c-b704974e44da', 'sources': 1}, {'artists': [{'id': '10bf95b6-30e3-44f1-817f-45762cdc0de0', 'name': 'Paradise Lost'}], 'duration': 346, 'id': 'f3699df7-1361-4c0a-b4c0-cf67baf6d2a3', 'releasegroups': [{'id': 'c7632b5e-fa15-4a8f-b388-19541c16ed27', 'releases': [{'country': 'US', 'date': {'day': 15, 'month': 5, 'year': 2020}, 'id': 'be133eae-bd85-40c1-aefc-2ad3135cb5aa', 'medium_count': 1, 'mediums': [{'format': 'CD', 'position': 1, 'track_count': 11, 'tracks': [{'id': 'b28a587a-0f42-4545-aac3-a19f58d89c0b', 'position': 1}]}], 'releaseevents': [{'country': 'US', 'date': {'day': 15, 'month': 5, 'year': 2020}}], 'track_count': 11}, {'country': 'XE', 'date': {'day': 26, 'month': 6, 'year': 2020}, 'id': '1e4bf102-7999-48ef-9093-ca395134302d', 'medium_count': 1, 'mediums': [{'format': '12" Vinyl', 'position': 1, 'track_count': 9, 'tracks': [{'id': '8d867c0c-b9bd-481d-aa4d-f82b97db790e', 'position': 1}]}], 'releaseevents': [{'country': 'XE', 'date': {'day': 26, 'month': 6, 'year': 2020}}], 'track_count': 9}, {'country': 'XE', 'date': {'day': 15, 'month': 5, 'year': 2020}, 'id': '86475814-e56b-4949-991d-1e6a949fa195', 'medium_count': 1, 'mediums': [{'format': 'CD', 'position': 1, 'track_count': 9, 'tracks': [{'id': 'b0258a1f-111a-436a-a8a6-1f55970a6340', 'position': 1}]}], 'releaseevents': [{'country': 'XE', 'date': {'day': 15, 'month': 5, 'year': 2020}}], 'track_count': 9}, {'country': 'XE', 'date': {'day': 15, 'month': 5, 'year': 2020}, 'id': 'd504970c-abf5-4d67-b472-a1b350523439', 'medium_count': 1, 'mediums': [{'format': 'CD', 'position': 1, 'track_count': 11, 'tracks': [{'id': '87f5c553-2526-4337-beec-32c69a609e67', 'position': 1}]}], 'releaseevents': [{'country': 'XE', 'date': {'day': 15, 'month': 5, 'year': 2020}}], 'track_count': 11}, {'country': 'XE', 'date': {'day': 15, 'month': 5, 'year': 2020}, 'id': 'b0776ef9-92da-48a7-a630-cd8f45daea67', 'medium_count': 1, 'mediums': [{'format': '12" Vinyl', 'position': 1, 'track_count': 9, 'tracks': [{'id': 'ee01a897-1ac5-41bf-b04a-a0c48f1b87b9', 'position': 1}]}], 'releaseevents': [{'country': 'XE', 'date': {'day': 15, 'month': 5, 'year': 2020}}], 'track_count': 9}, {'country': 'JP', 'date': {'day': 15, 'month': 5, 'year': 2020}, 'id': '3c7db091-7c02-498a-a655-563f4116156b', 'medium_count': 1, 'mediums': [{'format': 'CD', 'position': 1, 'track_count': 9, 'tracks': [{'id': 'ecaf98a6-162d-43b9-aed1-eec53e6568cc', 'position': 1}]}], 'releaseevents': [{'country': 'JP', 'date': {'day': 15, 'month': 5, 'year': 2020}}], 'track_count': 9}, {'country': 'XW', 'date': {'day': 15, 'month': 5, 'year': 2020}, 'id': '1dd9a32b-1a40-4da3-88ab-c34d1fa1e7f6', 'medium_count': 1, 'mediums': [{'format': 'Digital Media', 'position': 1, 'track_count': 11, 'tracks': [{'id': 'ba1f1afb-f4b0-4884-a1d3-7b61d42e6436', 'position': 1}]}], 'releaseevents': [{'country': 'XW', 'date': {'day': 15, 'month': 5, 'year': 2020}}], 'track_count': 11}], 'title': 'Obsidian', 'type': 'Album'}], 'sources': 67, 'title': 'Darker Thoughts'}], 'score': 0.942774}], 'status': 'ok'}
Currently this breaks lookup in Picard for newer submissions. I can't say for sure if all submissions are affected or since when, but from what I experienced myself it seems to be rather consistent.