how to upgrade multi mds but not change it to single mds?

hi: Our Ceph cluster is deployed using Ceph cephadm and uses multiple MDS daemons. The documentation says that during a cephadm upgrade, the filesystem should be reduced to a single active MDS. However, this is not feasible for us(single mds have not enough mem). Is there a more elegant way to perform the upgrade? Thank you very much.