VMAX10K: Is there a way to add new devs and tgt's to an existing device group without causing delay in the recreation of the existing clones in the group?

Trying to add 8 new devs and 8 new tgt's to an existing device group.  This is for our main database server that uses these clones to do a nightly backup.  The database is frozen and then a activate and recreate is run nightly.  I am concerned with adding 8 new devs/tgt's that the activate / recreate will take a significant amount of time longer and cause our main application to be down while it initially syncs these new devices.

I am also looking for the syntax to add devs and tgt's to the group once it has already been created and in use.  To create the group a few years ago I used the following syntax.

symdg create prod_clone01 -type any

symdg -sid xxx -g prod_clone01 addall -devs xxx1,xxx2,xxx3,xxx4,xxx5,xxx6,xxx7,xxx8

symdg -sid xxx -g prod_clone01 -tgt addall -devs xxx9,xx10,xx11,xx12,xx13,xx14,xx15,xx16

symclone -g prod_clone01 create -tgt -nop -v

symclone -g prod_clone01 -tgt activate

symclone -g prod_clone01 -tgt recreate

Thanks!