I am in a not too dissimilar position to yourself (role/team size). I am working 4 days one week, 5 days the next (90% hours). It work out to be a nice comprom

I am in a not too dissimilar position to yourself (role/team size). I am working 4 days one week, 5 days the next (90% hours). It work out to be a nice compromise. The cross functional does not take too much of a hit, but the boost in productivity (IMHO) is still present. I have some push back about the arrangement from people two or three links away from me and my team output and I have not got metrics to prove that this is effective. Do you have any push back about your devs - 4 days 8 hours and 30% ? Do you have any other evidence/metrics for the benefits ?