I got those messages also the other day, I was working in assembly mode, with "no imprints" and had defined boundary conditions with boolean limits, using ALE on one side of the geometry, with force analysis on one part.
When I mesh coarse I get the message, by meshing finer they did not appear.
From what I got out, was that some of the ALE nodes were moving in and out of my boundary conditions settings, the solver detected that it should also inlcude/substract new/old nodes for the force clculations, but it was not able to "on the fly" during solving. The force measurements were also somewhat wrong, but the rest seemed to solve OK.
by decreasing mesh size, I did not get any warnings and the results seemd better.
Normally I start with a coarse mesh, and decrease until I have less than 10% changes on the results, while I check the warnings and other