space PR sends out over the whole epoch duration

mixing/mixclient/client.go

@@ -45,7 +45,6 @@ const (
 	maxJitter       = timeoutDuration / 10
 	msgJitter       = 15 * time.Millisecond
 	peerJitter      = maxJitter - msgJitter
-	extraPRJitter   = 30 * time.Second
 )
 
 // expiredPRErr indicates that a dicemix session failed to complete due to the
@@ -532,13 +531,14 @@ func (p *peer) msgJitter() time.Duration {
 func (c *Client) prDelay(ctx context.Context, p *peer) error {
 	now := time.Now().UTC()
 	epoch := now.Truncate(c.epoch).Add(c.epoch)
-	sendBefore := epoch.Add(-timeoutDuration - maxJitter - extraPRJitter)
+	sendBefore := epoch.Add(-timeoutDuration - maxJitter)
 	sendAfter := epoch.Add(timeoutDuration)
 	var wait time.Duration
 	if now.After(sendBefore) {
 		wait = sendAfter.Sub(now)
+		sendBefore = sendBefore.Add(c.epoch)
 	}
-	wait += p.msgJitter() + uniform.Duration(cryptorand.Reader, extraPRJitter)
+	wait += p.msgJitter() + uniform.Duration(cryptorand.Reader, time.Until(sendBefore))
 	timer := time.NewTimer(wait)
 	select {
 	case <-ctx.Done():