key signature issue in 3.0.1

I'm having an issue with a key signature change in the middle of a piece since updating to 3.0.1. I have a piece that changes from A flat major to C major in the middle of several bars of rest.

When I first make any change, such as turning on multi-measure rests or altering style settings, it displays correctly and shows the naturals when changed to C Major as displayed in the first image. As soon as I save the file it disappears and does not show the naturals when it changes to C Major. It changes key at letter P and I want this change to be marked with naturals. It does this no matter which option I have selected in the style settings for accidentals. When I save the file the naturals to indicate C Major disappear at letter P.