Credit Card Fee Applied After Upgrading Product

[#1]

Much like BodOrange in an earlier topic, I have just switched from Broadband Your Way Option Two to Plusnet Extra.
I see that my credit card has been billed for £11.49 + £1.50 credit card surcharge.  As an existing customer I was under the impression from the emails I'd received in December and 11th January (the day before the tariff change) that the surcharge was going to come into effect from 1st February.
I was intending to move to Direct Debit but thought I'd wait until the tariff upgrade had gone through, believing that I still had 3 weeks to make the change to DD.
Why was the credit card surcharge applied early and why wasn't I notified in advance that this would happen?

[#2]

It's a bug - the system is treating you as a new user for whom the extra fee was applied from January.
I don't understand why they haven't made a service status announcement on this, or identified and emailed all those affected.

[#3]

So that's the admin cost of switching products, plus the transaction fee of £1.50 plus crediting the money back to the customer and another transaction fee of £1.50p. 

[#4]

Raised a support ticket.  Was told that the credit charge surcharge would stand - justification was the automatic email (ticket) sent on the day of the tariff change.
Complained further.  Ticket escalated.  Am now told I will get a £1.50 credit on my next monthly bill.
Honour satisfied, I guess.

[#5]

FYI,
I've had a look at your account, I'm just sorry that this was dealt with in rather a clunky and ineffective way, feedback with be given to those who could have done better.
Also the issue which caused the charge is due to be resolved very soon so you should not be impacted by this any further.