First we had floods of biblical proportions, then the Wuhan Flu and now a plague of beetles. The little insects flying into your face or dropping down the back of your shirt collar are heather beetles, aka Lochmaea suturalis:
The larvae of the beetle feed on heather shoots and therefore damage the plants, which is why last year there was comparatively little purple up on our moors and great swathes of brown, sickly heather plants instead.