Box One Prime 9 Chain $$$$

Installed this new chain 3 rides ago when I switched from gears to SS and must re-tension each time before the next ride, I have not rode SS for three years and do not remember having to do this to my 2 other SS when I still had them before each ride. Is this common for this brand chain or is it still in a break in process , anyone else use this expensive chain ? I weigh 210 and my ride is between 10-15 miles with 1200-1500 feet of climbing, gearing is 30x20 the bike is a 2021Surly Karate Monkey using a Surly snuggnut on the drive side and the rear axle bolt is torqued to spec. When I re-tension the chain I only have to turn the thumb screw on the snuggnut about a 1/4 of a turn to take up the slack.