diff --git a/restructuring/analysis/facts/priority_inversion_is_bounded.v b/restructuring/analysis/facts/priority_inversion_is_bounded.v
index 6fbe1590ccd8591675a6b9eaff95f007a2c8398d..9e7880b5648255ffe036ca2d29d4f9a9042a5483 100644
--- a/restructuring/analysis/facts/priority_inversion_is_bounded.v
+++ b/restructuring/analysis/facts/priority_inversion_is_bounded.v
@@ -18,6 +18,72 @@ From mathcomp Require Import ssreflect ssrbool eqtype ssrnat seq path fintype bi
     pending jobs are always ready. *)
 Require Import rt.restructuring.model.readiness.basic.
 
+(** In preparation of the derivation of the priority inversion bound, we
+    establish two basic facts on preemption times. *)
+Section PreemptionTimes.
+
+  (** Consider any type of tasks ... *)
+  Context {Task : TaskType}.
+  Context `{TaskCost Task}.
+  Context `{TaskMaxNonpreemptiveSegment Task}.
+
+  (**  ... and any type of jobs associated with these tasks. *)
+  Context {Job : JobType}.
+  Context `{JobTask Job Task}.
+  Context `{JobArrival Job}.
+  Context `{JobCost Job}.
+
+  (** In addition, we assume the existence of a function mapping a
+      task to its maximal non-preemptive segment ... *)
+  Context `{TaskMaxNonpreemptiveSegment Task}.
+
+  (** ... and the existence of a function mapping a job and
+      its progress to a boolean value saying whether this job is
+      preemptable at its current point of execution. *)
+  Context `{JobPreemptable Job}.
+
+  (** Consider any arrival sequence with consistent arrivals. *)
+  Variable arr_seq : arrival_sequence Job.
+  Hypothesis H_arrival_times_are_consistent : consistent_arrival_times arr_seq.
+
+  (** Next, consider any ideal uniprocessor schedule of this arrival sequence ... *)
+  Variable sched : schedule (ideal.processor_state Job).
+  Hypothesis H_jobs_come_from_arrival_sequence:
+    jobs_come_from_arrival_sequence sched arr_seq.
+
+  (** Consider a valid model with bounded nonpreemptive segments. *)
+  Hypothesis H_model_with_bounded_nonpreemptive_segments:
+    valid_model_with_bounded_nonpreemptive_segments arr_seq sched.
+
+  (** Then, we show that time 0 is a preemption time. *)
+  Lemma zero_is_pt: preemption_time sched 0.
+  Proof.
+    unfold preemption_time.
+    case SCHED: (sched 0) => [j | ]; last by done.
+    move: (SCHED) => /eqP; rewrite -scheduled_at_def; move => ARR.
+    apply H_jobs_come_from_arrival_sequence in ARR.
+    rewrite /service /service_during big_geq; last by done.
+    destruct H_model_with_bounded_nonpreemptive_segments as [T1 T2].
+    by move: (T1 j ARR) => [PP _].
+  Qed.
+
+  (** Also, we show that the first instant of execution is a preemption time. *)
+  Lemma first_moment_is_pt:
+    forall j prt,
+      arrives_in arr_seq j ->
+      ~~ scheduled_at sched j prt ->
+      scheduled_at sched j prt.+1 ->
+      preemption_time sched prt.+1.
+  Proof.
+    intros s pt ARR NSCHED SCHED.
+    unfold preemption_time.
+    move: (SCHED); rewrite scheduled_at_def; move => /eqP SCHED2; rewrite SCHED2; clear SCHED2.
+    destruct H_model_with_bounded_nonpreemptive_segments as [T1 T2].
+    by move: (T1 s ARR) => [_ [_ [_ P]]]; apply P.
+  Qed.
+
+End PreemptionTimes.
+
 (** * Priority inversion is bounded *)
 (** In this module we prove that any priority inversion that occurs in the model with bounded 
     nonpreemptive segments defined in module rt.model.schedule.uni.limited.platform.definitions 
diff --git a/restructuring/model/preemption/preemption_time.v b/restructuring/model/preemption/preemption_time.v
index 37bf755904ecd8b9fc47c52eda9c08cb994d996d..dfe6e24e18a6346428a2061bd37280fc03620dfb 100644
--- a/restructuring/model/preemption/preemption_time.v
+++ b/restructuring/model/preemption/preemption_time.v
@@ -1,6 +1,5 @@
 Require Import rt.util.all.
 Require Import rt.restructuring.behavior.all.
-Require Import rt.restructuring.analysis.basic_facts.ideal_schedule.
 Require Import rt.restructuring.model.job.
 Require Import rt.restructuring.model.task.
 Require Import rt.restructuring.model.processor.ideal.
@@ -50,41 +49,5 @@ Section PreemptionTime.
     if sched t is Some j then
       job_preemptable j (service sched j t)
     else true.
-  
-  (** In this section we prove a few basic properties of the preemption_time predicate. *)
-  Section Lemmas.
-
-    (** Consider a valid model with bounded nonpreemptive segments. *)
-    Hypothesis H_model_with_bounded_nonpreemptive_segments: 
-      valid_model_with_bounded_nonpreemptive_segments arr_seq sched. 
-
-    (** Then, we show that time 0 is a preemption time. *)
-    Lemma zero_is_pt: preemption_time 0.
-    Proof.
-      unfold preemption_time.
-      case SCHED: (sched 0) => [j | ]; last by done.
-      move: (SCHED) => /eqP; rewrite -scheduled_at_def; move => ARR. 
-      apply H_jobs_come_from_arrival_sequence in ARR.
-      rewrite /service /service_during big_geq; last by done.
-      destruct H_model_with_bounded_nonpreemptive_segments as [T1 T2].
-        by move: (T1 j ARR) => [PP _]. 
-    Qed.
-
-    (** Also, we show that the first instant of execution is a preemption time. *)
-    Lemma first_moment_is_pt:
-      forall j prt,
-        arrives_in arr_seq j ->
-        ~~ scheduled_at sched j prt ->
-        scheduled_at sched j prt.+1 ->
-        preemption_time prt.+1.
-    Proof. 
-      intros s pt ARR NSCHED SCHED.
-      unfold preemption_time.
-      move: (SCHED); rewrite scheduled_at_def; move => /eqP SCHED2; rewrite SCHED2; clear SCHED2.
-      destruct H_model_with_bounded_nonpreemptive_segments as [T1 T2].
-        by move: (T1 s ARR) => [_ [_ [_ P]]]; apply P.
-    Qed.
-
-  End Lemmas.
     
 End PreemptionTime.