Upon Saving lately stair stepped looking then 'ok'

Something I’ve noticed, that happens sometimes, is when I save all, the terrain temporarily becomes stair stepped and irregular, then after a moment its fine,tho sometimes I’ve had to exit and restart, all this in 4.24.1. Is this an indication of anything ? Bug, memory,GPU etc., or something else…I’d like to double check is all to avoid problems , if this is,farther down the road. I’ll try and take a pic if needed.