I remember in the early '80s having to phone the tower at BK and book a slot for night circuits. Worked fine - but then they had enough staff back then to run the booking system as well as the TWR!
A rather ominous NOTAM just promulgated for BK:
C322/09
START APPROVAL REQUIRED FOR CIRCUIT OPERATIONS
FROM 07 200052 TO PERM
Note it is effective permanently.