I am unsure. Please try changing the plan via selfcare. Sometimes, it gets accepted automatically. I remember one of the forum members has switched to one of the promotional plans even if they are available only for new customers or for customers who has only telephone facility. That particular forum member has had broadband facility for long.
If selfcare accepts the change of plan (to 491), then after one month, you may try to change the plan to another lower priced plan. We just need a bit of luck (with selfcare or with CSC). It is possible to convince people at CSC of our needs. Most people in CSC these days in a couple of exchanges near me are very friendly that is unusual (compared to a few years ago).
