diff --git a/src/operations.jl b/src/operations.jl
index b0e51ff..c6ba2ce 100644
--- a/src/operations.jl
+++ b/src/operations.jl
@@ -110,13 +110,14 @@ function amr_get(df::DataFrame, sys::ODESystem, ::Val{:data})
 end
 
 #--------------------------------------------------------------------# IntermediateResults callback
-# Publish intermediate results to RabbitMQ with at least `every` seconds inbetween callbacks
+# Publish intermediate results to RabbitMQ with at least `every` seconds in between callbacks
 mutable struct IntermediateResults
     last_callback::Dates.DateTime  # Track the last time the callback was called
     every::Dates.TimePeriod  # Callback frequency e.g. `Dates.Second(5)`
     id::String
+    iter::Int # Track how many iterations of the calibration have happened
     function IntermediateResults(id::String; every=Dates.Second(0))
-        new(typemin(Dates.DateTime), every, id)
+        new(typemin(Dates.DateTime), every, id, 0)
     end
 end
 
@@ -134,6 +135,17 @@ function (o::IntermediateResults)(integrator)
     EasyModelAnalysis.DifferentialEquations.u_modified!(integrator, false)
 end
 
+# Intermediate results functor for calibrate
+function (o::IntermediateResults)(p,lossval,ode_sol)
+    if o.last_callback + o.every ≤ Dates.now()
+        param_dict = Dict(parameters(ode_sol.prob.f.sys) .=> ode_sol.prob.p)
+        state_dict = Dict([state => ode_sol[state] for state in states(ode_sol.prob.f.sys)])
+        o.iter = o.iter + 1
+        publish_to_rabbitmq(; iter = o.iter, loss = lossval, sol_data = state_dict, params = param_dict, id=o.id)
+    end
+
+    return false
+end
 #----------------------------------------------------------------------# dataframe_with_observables
 function dataframe_with_observables(sol::ODESolution)
     sys = sol.prob.f.sys
@@ -158,8 +170,7 @@ function Simulate(o::OperationRequest)
 end
 
 function get_callback(o::OperationRequest, ::Type{Simulate})
-    DiscreteCallback((args...) -> true, IntermediateResults(o.id,every = Dates.Second(0)),
-                                                    save_positions = (false,false))
+    DiscreteCallback((args...) -> true, IntermediateResults(o.id,every = Dates.Second(0)))
 end
 
 # callback for Simulate requests
@@ -184,11 +195,7 @@ end
 
 # callback for Calibrate requests
 function get_callback(o::OperationRequest, ::Type{Calibrate})
-    function (p,lossval,ode_sol)  
-        param_dict = Dict(parameters(ode_sol.prob.f.sys) .=> ode_sol.prob.p)
-        state_dict = Dict([state => ode_sol[state] for state in states(ode_sol.prob.f.sys)])
-        publish_to_rabbitmq(; loss = lossval, sol_data = state_dict, params = param_dict, id=o.id)
-    end
+    IntermediateResults(o.id,every = Dates.Second(0))
 end
 
 function Calibrate(o::OperationRequest)