Yes eventually all trains will get LHB rake but providing LHB rake to all trains will not be completed before the next 20-30 years or may be more than that also. Till then these ICF rakes can be used.
If Ratna exp gets LHB, then these upgraded rakes can be given to some other train like asn Cst exp, asn gd exp, asn gkp exp. When those trains will also get LHB, these rakes can be transferred to some other division and their trains can used these rakes