Vanishing Lot contents

Sims 4 - since the March 23rd patch I have suffered disappearing buildings, despite frequent saves, especially from the Newcrest world, but elsewhere as well. For example, my Washburn family live in Newcrest and own two restaurants and a skating rink spread around several worlds. Their entire empire has vanished which is most annoying. All was perfectly fine after all the recent updates until March 23rd. Anyone any ideas? Is this me, or have others found this happening?