All of the following are true about the recent measles outbreaks EXCEPT:
So far in 2024 (as of January 25), CDC reports 9 measles cases in 4 jurisdictions: Georgia, Missouri, New Jersey, and Pennyslvania.
It typically takes about 4 to 6 days for initial symptoms to appear after exposure.
In 2023, a total of 58 measles cases were reported by 20 jurisdictions.
In the U.K. a measles outbreak continues to widen: There have been 216 confirmed cases and 103 probable cases reported since October.
Lower MMR vaccination rates can put unvaccinated and undervaccinated individuals at risk, especially children and those with immune system problems.
You are correct. The incubation period for measles is 10 to 12 days. Because of this, most infected people assume their respiratory symptoms are nothing but a cold until the rash appears three to five days after the initial illness begins.

Sources:

(Last reviewed 2024, January 26). CDC. Measles (Rubeola). Measles Cases and Outbreaks. https://www.cdc.gov/measles/cases-outbreaks.html

Musa, A. and Hassan, C. (2024, January 23). CNN. Why are measles cases popping up across the United States? Here's what to know about the highly contagious virus. https://www.cnn.com/2024/01/23/health/measles-cases-xpn-wellness/index.html