Qatar called two days before the flight to say arrive 4 hours early as some people had missed flights due to long security queues at LHR.
I was advised on here to check in online (from 48 before) and print boarding pass beforehand.
I arrived 5 hours before, no wait to drop off my bag and through security in 30 mins. No forveveryone but suits me😃ps Strangely no security before 2nd flight🤔
Quite easy to do, although looks more in involved than it is. Once I had submitted it (London Embassy), apart from a small query they had, it was issued within 2 days.