Has Strava Changed how RE and fitness score is calculated?

I’ve been very gradually marathon training for the last 4 months. 3days per week. Started running abut 15 miles per week and have gotten myself up to 29mi/wk. I also strength train 3 times per week and usually get in some sort of hike or swim. Since the marathon training, my fitness score has steadily risen from 23 to 46. I've have also consistently kept my relative effort within the recommended maintenance zone OR above it.

But something changed a few weeks ago.

I decided to take a deload week just before adding a 4th run to my training schedule. Went from a 29mi week to a 22mi week. As expected, my RE and fitness scores dipped. But when I returned to my regular intensity with an additional run, my scores just kept dropping. Id repeat the exact same runs that I did weeks prior (with the same heart rate, same pace, same time, same terrain, same route) but my RE score would be half of what they were just a a couple weeks prior.

Even adding in a 4th run and upping my mileage to 35mi/wk, my RE and fitness scores are still steadily dropping. I even did a 1.5mi ocean swim race after a 35mi/wk and with 3 strength training days and my scores just went down.

I would understand if my efforts were lower, but I pay attention to my heart rate like a hawk during my runs to make sure Im maintaining a consistent effort level. So my heart rate data is identical to my runs during the months when my fitness scores were steadily rising and I consistently stayed within the RE goal zone.

My fitness score has dropped from 46 to 37 in 4 weeks. But if you look at all of my HR data, total run time, total mileage, total strength training time, and total swim time, I’m exercising more harder than I was when that score was rising. Ive even lost fat and gained muscle during the last 4 weeks.

I’m not concerned about my health. I know I’m doing great. But one of the reasons I love Strava is because I could use the fitness scores and RE scores as reflections of my effort. When they rise, I’d pat myself on the back. When they drop, I’d use that as motivation to get back on track. Now the scores or just a source of confusion and demotivation.

What’s happening?

PS. I track all of my workouts on my Garmin Forerunner 965 and they automatically upload to Strava. not sure if that makes a difference. But my bio tracker info on Garmin has remain unchanged, so I figure this is happening on Strada’s end.