So this means that if you have a rate with multiple periods within a month, and the tier maxes (kWh) vary between those periods, REopt will overwrite the tier max values for all periods that are not the hour 1 period, using hour 1 period maxes.

For example, period 1 here would be assumed to have a 1st tier max of 88 in May-Sept, and a 1st tier max of 100 in Nov (given the resulting energy_tier_limits matrix shown below); is that a correct interpretation?
energy_tier_limits_kwh: [88.0 1.0e10; 88.0 1.0e10; 88.0 1.0e10; 88.0 1.0e10; 88.0 1.0e10; 88.0 1.0e10; 88.0 1.0e10; 88.0 1.0e10; 88.0 1.0e10; 88.0 1.0e10; 100.0 1.0e10; 88.0 1.0e10]

Is it accurate to say this is still not fully capturing the intended rate, but is one step better than what we did before, which was assume that all periods[tiers] had the same max limits?

So this means that if you have a rate with multiple periods within a month, and the tier maxes (kWh) vary between those periods, REopt will overwrite the tier max values for all periods that are not the hour 1 period, using hour 1 period maxes.

For example, period 1 here would be assumed to have a 1st tier max of 88 in May-Sept, and a 1st tier max of 100 in Nov (given the resulting energy_tier_limits matrix shown below); is that a correct interpretation? energy_tier_limits_kwh: [88.0 1.0e10; 88.0 1.0e10; 88.0 1.0e10; 88.0 1.0e10; 88.0 1.0e10; 88.0 1.0e10; 88.0 1.0e10; 88.0 1.0e10; 88.0 1.0e10; 88.0 1.0e10; 100.0 1.0e10; 88.0 1.0e10]

Is it accurate to say this is still not fully capturing the intended rate, but is one step better than what we did before, which was assume that all periods[tiers] had the same max limits?

That's correct if we are talking about monthly rates and limits, but the time-of-use "ratchets" allow for custom definition of periods and so this setup likely assigns a separate "ratchet" that consists of thirty hourly periods from 12-1am and another for all the other hours in November, each of which has its own separate tiers and limits. I'd expect to see 18 time-of-use periods in this setup, each of which has two tiers.

So, to that end: is the above matrix what's actually produced when you insert this custom output or do you get the 2x18 matrix? One thing I did not touch as part of this PR is the logic for when custom time-of-use vs. monthly tiers are generated. We can revisit that, but it's likely best reserved for an issue at this point.

piggybacking on this comment: what I said above applies to demand charges but not energy rates, so this is a missing feature as compared to everything that the URDB rate builder allows for.