Average Speed Cameras / Speed Signs

Dear sir or madam,

Last week when I drove through the road works at the above location I noticed the speed limit was 20 mph in both directions, this week I have noticed that it has increased to 40 mph. Can I confirm what the speed limit is please as although the 20 mph signs have been removed (in both directions) some of the 40 mph signs are blanked out. Can i confirm the cameras have also now been set to the 40 mph rather than the 20? I drove through there over the last few days at approximately 20 mph as I wasn’t sure, but was flashed by almost every car behind me, including buses, taxi and embarrassingly an an ambulance (obviously not on blues)

I feel it needs to made clear what the speed limit is there, especially if it has recently been increased.