@MarcoGorelli suggested in https://github.com/pandas-dev/pandas/pull/51459#pullrequestreview-1347005695 to add more tests for Period repr before #51459 can be merged.

What I'm most concerned about is that not all these reprs seems to be explicitly tested for. Some of them are, e.g. https://github.com/pandas-dev/pandas/blob/044227f25bfbf61a9b7833c15538f8af26bfb89d/pandas/tests/scalar/period/test_period.py#L711-L719 but then FR_SEC isn't (as far as I can tell).

Reckon we should add such unit tests for each period group (perhaps in a separate PR, which we could get in very quickly)? That would give me much more confidence about merging this