To improve the chances of the application being approved, wouldn't they try to keep the tilt enabled on the Class 221s? If a Wrexham service is followed by a Class 390 departing only three minutes later, the 390 would surely catch up by the time they reach Rugby if the 221 has its tilt isolated. Furthermore, didn't the 221s have different EPS (Enhanced Permissible Speed) limits compared to the 390s?I thought they were being backed by Alstom, who are/were holding the 6x (?) remaining ex Avanti 221s...
