I just got back from a long trip & I don't recall exactly where they were, but I've created 2 test cases.
locus version 3.35.2
desert center N 33.713176 115.400324 to
W 33.6666, 112.3255
brouter, brouter profile, fast, or brouter, locus profile car-fast
At 47.9 and 173 mi ( 77, 278km) , the router exits the highway and gets back on.
Using graphhopper, Car, same start and end, doesn't have the exit & reentry, but has some extra/confusing guidance at 68.8 and161 mi (111 and 259 km)
Using Graphhopper. Car
ElCajon, CA, USA, 32.79477 116.962527 to
Yuma, AZ, USA, 32.725325 114.624397
Extra/confusing guidance at 62.9 and 152 mi (101, 245 km)