diff --git a/src/core/time.jl b/src/core/time.jl
index 03496c2b6..fe15a34fc 100644
--- a/src/core/time.jl
+++ b/src/core/time.jl
@@ -125,6 +125,14 @@ function Base.:+(ts::VariableTimestep{TIMES}, val::Int) where {TIMES}
 	new_ts = VariableTimestep{TIMES}(ts.t + val)
 end
 
+function Base.:-(ts::Timestep, val::Int) 
+	return Timestep(ts.value, ts.offset_in_timesteps - val)
+end
+
+function Base.:+(ts::Timestep, val::Int) 
+	return Timestep(ts.value, ts.offset_in_timesteps + val)
+end
+
 #
 #  2. CLOCK
 #
@@ -195,6 +203,20 @@ function _missing_data_check(data)
 	end
 end 
 
+# Helper functions for Timestep type
+function _get_time_value_position_(times::Array, ts::Timestep)
+	t = findfirst(isequal.(ts.value, times))
+	if t === nothing
+		error("cannot use Timestep with value $(ts.value), value is not in the TimestepArray")
+	end
+	
+	t_offset = t + ts.offset_in_timesteps
+	if t_offset > length(times) 
+		error("cannot get offset of $(ts.offset_in_timesteps) from $(ts.value), offset is after the end of the TimestepArray")
+	end
+	return t_offset
+end
+
 # Helper macro used by connector 
 macro allow_missing(expr)
 	let e = gensym("e")
@@ -239,6 +261,18 @@ function Base.getindex(v::TimestepVector{VariableTimestep{D_TIMES}, T}, ts::Vari
 	_missing_data_check(data)
 end
 
+function Base.getindex(v::TimestepVector{FixedTimestep{FIRST, STEP, LAST}, T}, ts::Timestep) where {T, FIRST, STEP, LAST} 
+	t = _get_time_value_position_([FIRST:STEP:LAST...], ts)
+	data = v.data[t]
+	_missing_data_check(data)
+end
+
+function Base.getindex(v::TimestepVector{VariableTimestep{TIMES}, T}, ts::Timestep) where {T, TIMES}
+	t = _get_time_value_position_(TIMES, ts)
+	data = v.data[t]
+	_missing_data_check(data)
+end
+
 # int indexing version supports old-style components and internal functions, not
 # part of the public API
 
@@ -333,6 +367,30 @@ function Base.getindex(mat::TimestepMatrix{VariableTimestep{D_TIMES}, T, 2}, idx
 	_missing_data_check(data)
 end
 
+function Base.getindex(mat::TimestepMatrix{FixedTimestep{FIRST, STEP, LAST}, T, 1}, ts::Timestep, idx::AnyIndex) where {T, FIRST, STEP, LAST} 
+	t = _get_time_value_position_([FIRST:STEP:LAST...], ts)
+	data = mat.data[t, idx]
+	_missing_data_check(data)
+end
+
+function Base.getindex(mat::TimestepMatrix{VariableTimestep{TIMES}, T, 1}, ts::Timestep, idx::AnyIndex) where {T, TIMES}
+	t = _get_time_value_position_(TIMES, ts)
+	data = mat.data[t, idx]
+	_missing_data_check(data)
+end
+
+function Base.getindex(mat::TimestepMatrix{FixedTimestep{FIRST, STEP, LAST}, T, 2}, idx::AnyIndex, ts::Timestep) where {T, FIRST, STEP, LAST} 
+	t = _get_time_value_position_([FIRST:STEP:LAST...], ts)
+	data = mat.data[idx, t]
+	_missing_data_check(data)
+end
+
+function Base.getindex(mat::TimestepMatrix{VariableTimestep{TIMES}, T, 2}, idx::AnyIndex, ts::Timestep) where {T, TIMES}
+	t = _get_time_value_position_(TIMES, ts)
+	data = mat.data[idx, t]
+	_missing_data_check(data)
+end
+
 
 function Base.setindex!(mat::TimestepMatrix{FixedTimestep{FIRST, STEP}, T, 1}, val, ts::FixedTimestep{FIRST, STEP, LAST}, idx::AnyIndex) where {T, FIRST, STEP, LAST} 
 	setindex!(mat.data, val, ts.t, idx)
@@ -449,6 +507,18 @@ function Base.getindex(arr::TimestepArray{VariableTimestep{D_TIMES}, T, N, ti},
 	return arr.data[idxs1..., t, idxs2...]
 end
 
+function Base.getindex(arr::TimestepArray{FixedTimestep{FIRST, STEP, LAST}, T, N, ti}, idxs::Union{Timestep, AnyIndex}...) where {T, N, ti, FIRST, STEP, LAST}
+	idxs1, ts, idxs2 = split_indices(idxs, ti)
+	t = _get_time_value_position_([FIRST:STEP:LAST...], ts)
+	return arr.data[idxs1..., t, idxs2...]
+end
+
+function Base.getindex(arr::TimestepArray{VariableTimestep{TIMES}, T, N, ti}, idxs::Union{Timestep, AnyIndex}...) where {T, N, ti, TIMES}
+	idxs1, ts, idxs2 = split_indices(idxs, ti)
+	t = _get_time_value_position_(TIMES, ts)
+	return arr.data[idxs1..., t, idxs2...]
+end
+
 function Base.setindex!(arr::TimestepArray{FixedTimestep{FIRST, STEP}, T, N, ti}, val, idxs::Union{FixedTimestep{FIRST, STEP, LAST}, AnyIndex}...) where {T, N, ti, FIRST, STEP, LAST}
 	idxs1, ts, idxs2 = split_indices(idxs, ti)
 	setindex!(arr.data, val, idxs1..., ts.t, idxs2...)
diff --git a/src/core/types.jl b/src/core/types.jl
index bdbefc1b5..98f54e9ce 100644
--- a/src/core/types.jl
+++ b/src/core/types.jl
@@ -22,6 +22,15 @@ struct VariableTimestep{TIMES} <: AbstractTimestep
     end
 end
 
+struct Timestep <: AbstractTimestep
+    value::Int
+    offset_in_timesteps::Int
+
+    function Timestep(v::Int, offset_in_timesteps::Int=0)
+        return new(v, offset_in_timesteps)
+    end
+end
+
 mutable struct Clock{T <: AbstractTimestep}
 	ts::T