I will see if I can get up the energy to speak to them again today, otherwise I will call again on Friday (I am in the office tomorrow). At least that way I have left it for 2 days to see if things have resolved.
I'm with you, it looks like the patch has been applied to my HH% too but wireless devices are constantly struggling to connect, no problem with wired devices at all, also, my connection has been solid at 76-79mb for the last 13 months and since this update it has dropped to 61-62mb.
I spoke to BT (India) on Monday night, they checked the line and router and both seem fine, they will monitor it!!!