Which bookies are slowest to ban?
Assuming you are matched betting competently, and taking sustainability seriously, there are a number of bookies which you should be able to keep promos on for at least a few months e.g. Sportsbet, Tabtouch & Bet365.
It should be noted that the tides are constantly changing - what works at one bookie on one day, may not work the next day. The best way to keep on top of this is to be an active member of the discord, reading reports from others, as well as contributing with your own experiences. Some good channels to read through include: #bookie-info, #bookie-behaviour, #sustainability