Air Traffic Controller Shortages at London Gatwick Airport (EGKK)

The ASG has become concerned following the promulgation of NOTAM A1294/18 in the early hours of this morning at Gatwick Airport.
(A1294/18 NOTAMN
Q) EGTT/QSPLC/IV/BO /AE/000/025/5109N00011W014
A) EGKK B) 1804080040 C) 1804080420
E)
DUE SHORT NOTICE SICKNESS ALL GATWICK ATC SERVICES WILL BE SUSPENDED
BETWEEN THE HOURS OF 0100-0200 AND 0330-0400. AS A RESULT A ZERO
FLOW RATE WILL BE APPLIED FROM 0040-0220 AND 0310-0420.)
Enquiries as to why there was no staff sickness cover to maintain operational continuity should be addressed to Gatwick Airport Ltd.
What is a NOTAM :- A notice to airmen (NOTAM) is a notice containing information concerning the establishment, condition or change in any aeronautical facility, service, procedure or hazard, the timely knowledge of which is essential to personnel concerned with flight operations. (ICAO Annex 11: Air Traffic Services) https://www.skybrary.aero/index.php/Notice_To_Airmen_(NOTAM)