If your intention is to remain with BT for broadband only , and want to port your existing phone number to a traditional VoIP supplier, there are a few things to consider…if you simply ask a VoIP provider to port the number ( these things are instigated by the gaining provider not the losing provider ) , your broadband will be ceased as a consequence, you could restart your BT broadband service but obviously this will mean a period without service , you could arrange with BT to become a broadband only customer, but there is a recent post where to achieve this the BT customer had to be moved to EE ( pretty much an identical service so no great hardship ) once you are a stand-alone broadband customer (EE or BT ) the phone number is available to be ported for 30 days …this is entirely your chosen VoIP provider responsibility, if it fails , blame them.
As far as VoIP representing better value for your needs, care to share the company and plan, most VoIP providers I’ve seen charge more per month ( £10+ compared to BT £3 for PAYG ) , although their price per minute for calls is better , if you make a small number of calls the £7 difference isn’t likely to be covered, and if a large number of calls , then BT Unlimited calls plan is £12 , so although the VoIP is cheaper, it’s not by much .
Obviously the SH2 requirement may be reason enough to move telephony elsewhere, but you do then have the expense of providing your own ATA etc ..
