I don't think anything has changed. Look at the conditions. The Kiawah B9 RG has light winds, which is the reason for the uber low scores since last time switched it. When the winds are higher the scores are up a touch. That RG is a cakewalk at the moment. I posted a 30 yesterday and I played poorly outside of luckily making a few longer putts.
For example, looking at RG #3969, a pretty easy Kiawah full in moderate conditions, a 65 will get you tied for 3rd at the moment. That's not a low score at all and should be easily attained by many masters barring meter issues.
Some days you might get more competition than others. The luck of which tourny you enter plays a huge part. In addition the Masters just concluded, so perhaps there is more RG traffic for the last week or so.
Matter of fact, looking at all the closed tournaments right now, nothing looks overly low at all. Sounds like you just got a bad stretch of studmuffins in some of the RGs you've entered. Hope you have better luck next time.