UK Matz may not be active over the weekends, and sometimes during the week.
I flew over Shawbury one Thursday afternoon, and could not get a reply from several calls on their frequency. I continued through their Matz and gave a call on 121.5 for a radio check, they confirmed my radio was Ok. Maybe if they are short-staffed, they close for lunch. I think they also close at 16:00 hrs at the end of their duty.
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