Welcome to the Community Forum and thanks for your post. I'm sorry to hear that you are getting error C501 when accessing On Demand and that you haven't had any further update regarding landline capacity in your area.
For the landline installation issue, I have emailed our Telephone Operations Centre to chase this up for you. As soon as I have more information on this, I will get back in touch with you.
With your On Demand issue, please try the following:
Home > Help & Settings > Settings > Network > Connect to the Virgin Media Service now
Wait about 10 seconds--does it show here that the service connection failed or Network cable unplugged error?
If it shows connecting (loading), this could take up to 40 minutes to complete. Once this has completed, see if you can access On Demand.
Please let me know how you get on with this.
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