British Airways has announced, via its LinkedIn page (!), that it has re-opened the Galleries Club North lounge at Heathrow Terminal 5. It will be open from 5am until 2pm, after which you will have to go to the South lounge.
This is good news, because it means that traffic is picking up more quickly than the South lounges can cope with, especially with current social distancing measures in place. You can read more about the changes British Airways has made to its lounges, including the innovative food ordering system, in this article.
I’m not sure if the ‘secret’ Fast Track security lane at the North end of Terminal 5 is open (this is the Fast Track security lane which is totally separate to all of the others, virtually straight in front of you if you come out of the lifts from the tube or Heathrow Express). If it is you should now be able to get from terminal entrance to the North lounge in under 5 minutes with hand baggage.
The current online food ordering and delivery service is a genuine improvement on what was offered before. You can see a sample menu here.