Plants with multiple respondent frequencies

[grgmiller]

Generally, plants report data to EIA-923 for all of their parts at a single frequency: monthly data or annual data.

However, certain plants appear to report some of their data monthly (AM) and some data annually (A), such as plant 422:

We should check:

1. Is this correct that plants can report at different frequencies, or is this a typo?
2. If this multi-frequency reporting is correct, then is the way that the annual data is getting assigned to months correct? The way the EIA currently does this shaping is based on the monthly shape of generators with similar characteristics. However, if we have monthly data for part of the plant, would it be more realistic to assume that the part of the plant that reports annually follows a similar pattern to the plant that reports monthly?

Also, if it is the case that plants can have multiple reporting frequencies, we should figure out how to address this in pudl. Currently, reporting frequency is a plant-level attribute in the plants_eia860 table, but this might need to be updated.