Instant reaction to that is Bottle/Genii/Cork … but FR24 etc. would hopefully be shut down by Government diktat at the first opportunity. And shoot spotters!
When we at Waddington launched n Vulcans to Ascension in total r/t silence, with a Sov AGI perched off-shore, there were additional Sy procedures in place … I will not elaborate further., but my Aldis lamp justified it’s existence that day.
As to the nub of your question, COMSEC is the only possible option, aka STFU!