Whilst I understand the annoyance here, we stand by the process we're using which is that we'll only change the price if the customer contacts us or changes account type.
Then PlusNet doesn't deserve the rankings it has received for good Customer Service if that's the attitude (required, perhaps, by the Financial section, rather than the choice of customer-facing staff).
It's the sort of admission that needs reporting to Which? and brought up next time there are any awards being handed out. Bear it in mind that some of us could well do so. Not a criticism of you, personally, but of the policy adopted by PlusNet on this matter, and definitely detrimental to a subset of customers (though it would need someone inside PN to know what the numbers affected are).
If you run a business, have a second ISP and backup web hosting...
1996? Enterprise (IoM 0345) + Clara.net
1998? Clara.net + Freeserve
2000 Freeserve 500kbps (+ Clara dial-up + Clara USENET/Mail)
2002 ? Eclipse 500 kbps + FS
2003 ? UKFSN 1000 kbps + Eclipse
2005 ? PlusNet 8 Mbps+ Eclipse
moved home - used office BB
2008 Three dongle at home
2010 PlusNet 2 Mbps + Three dongle
2012 PN 10 Mbps + Three (ZTE 802.11 router) + Three mobile (802.11 hotspot)
2013 PN 30? Mbps + VM 30+? Mbps + Three mobile