Ten years is long enough to forget the chaos of covering campaigns during redistricting. But North Carolina, bless its heart, was kind enough to offer us an early taste of the upcoming craziness of a redistricting cycle.

First, new congressional lines can put new pressure on members.

One day, Republican Mark Walker was coasting to reelection in North Carolina’s 6th District, where Donald Trump received 56 percent of the vote in 2016. The next day, the congressman found himself in a district Hillary Clinton carried with 59 percent, according to calculations by Daily Kos Elections.

It’s a good example of how quickly a candidate’s prospects can change with a new map. Walker went from a likely fourth term in a race rated Solid Republican to dubious reelection prospects in a race rated Likely Democratic because of the new district lines. Now Walker must choose between running in a different (more Republican) district against a colleague, challenging GOP incumbent Thom Tillis in the Senate primary, or retiring and hanging up his cleats for the time being. (Walker was the starting pitcher for the Republicans in the 2018 congressional baseball game).

Faced with a similar situation and similar choices, 2nd District GOP Rep. George Holding decided not to run for reelection. He is a good example of why there tend to be more House retirements in redistricting cycles.

After 30 years in the House, California Republican David Dreier was greeted with a new congressional map that obliterated his district prior to the 2012 elections. California’s citizen redistricting commission divided his 26th District into six other seats, none with more than 32 percent of his old district. Dreier opted not to seek reelection.

This dynamic could also be a factor in the growing number of retirements this cycle. Some members might be calculating the time, energy and heartache necessary to win reelection in 2020, only to have their district be decimated next time around.

Second, new maps can alter the fight for the majority.

Thanks to intervention from a panel of state judges, Republicans who control the North Carolina legislature were forced to draw a new map that is viewed as more fair when compared to the partisanship of the state. The new map is likely to result in a delegation that consists of eight Republicans and five Democrats, instead of the current 10 Republicans and three Democrats. That means Republicans will likely need to gain two more seats next year in their effort to get back to the House majority. Instead of a net gain of 19 seats nationwide, they’re likely looking at a 21-seat gain necessary to oust Speaker Nancy Pelosi.

Confusion on district numbers

Third, redistricting can cause confusion with district numbers. Although the new North Carolina map kept the new numbers in roughly the same geographic area as the current district numbers, that’s not always the case.

For example, Pennsylvania’s 4th District for decades had been located north of Pittsburgh in the western part of the state. But after redistricting prior to the 2012 elections, the 4th District was about 200 miles east in York, with the 9th, 11th, 12th and 18th districts in between. And now, the 4th District is located further north in the western Philadelphia suburbs, after a new map was put in place before the 2018 elections.

Without knowing what the new maps will look like in 2022, we do know there will be some new district numbers to get used to. For example, Montana has had a single, at-large district for the last 30 years, but the state is expected to gain an additional seat during reapportionment, so there will be 1st and 2nd districts in Montana. There’s also likely to be an at-large district in Rhode Island. The Ocean State currently has two seats but will likely lose one because its population grew more slowly than the rest of the states over the last decade.

The new map in North Carolina won’t even be the same in two years. A new congressional district map will be drawn prior to the 2022 elections, when the Tar Heel State is expected to be allotted an additional, 14th, district.

Finally, the challenge and chaos of a redistricting cycle is not about specific members’ fates or new district numbers, but about the multitude of changes. If you thought North Carolina this year or Pennsylvania last year was confusing, just think about that over dozens of states. Even states that don’t gain or lose a seat will have new congressional lines based on population changes and partisanship of the cartographers.

But as we wait anxiously for next cycle’s chaos, we have new North Carolina lines to analyze this cycle, including new ratings where applicable:

1st District (G.K. Butterfield, D) — Solid Democratic 2nd District (Open, George Holding, R) — Likely Democratic (previously Leans Republican) 3rd District (Greg Murphy, R) — Solid Republican 4th District (David E. Price, D) — Solid Democratic 5th District (Virginia Foxx, R) — Solid Republican 6th District (Mark Walker, R) — Likely Democratic (previously Solid Republican) 7th District (David Rouzer, R) — Solid Republican 8th District (Richard Hudson, R) — Likely Republican (previously Solid Republican) 9th District (Dan Bishop, R) — Leans Republican (previously Toss-up) 10th District (Patrick T. McHenry, R) — Solid Republican 11th District (Mark Meadows, R) — Solid Republican 12th District (Alma Adams, D) — Solid Democratic 13th District (Ted Budd, R) — Solid Republican (previously Likely Republican)

Inside Elections contributing analyst Ryan Matsumoto contributed to this report.Nathan L. Gonzales is an elections analyst with CQ Roll Call.