Top: model for the ER and ORs assuming tilted circular rings. The position of the rings was fixed to the observations of Crotts & Heathcote (2000) (see text). Bottom: the tilted rings seen from the side. Light-echo paraboloids for 620 and 768 days after the explosion are shown. At those epochs the light-echo paraboloids intersect the ORs at the positions (named T1 and T2 in the upper panel, and named areas 4 and 1 in Table 9) observed through the FORS 1 and UVES slits.