When Husqvarna first started selling zero turns (they only had commercial models) the owners manual said 15 ps1 for front swivel tires. We quickly started getting calls from customers that a tire or two went flat. Found out they were popping off the bead.
So we repaired them with 30 psi, no more problems. Shortly after, Husqvarna Corp sent us a letter to start using 25psi. The manuals were updated later.