Same here too! Edinburgh to York is fine. York to Doncaster is a no no.
Has anyone noticed any strange and sudden speed restrictions as well?
I did a test run from Edinburgh to York and not far from Edinburgh whilst thrashing my Azuma at 85mph
a sudden an invisible undocumented 10mph restriction caught me speeding! Also similar happens whilst just after crossing pointwork at Doncaster. Another undocumented speed restriction!