Have BT changed IP Profile thresholds?

I normally sync around 56xx-57xx which means my IP Profile can change between 4500 and 5000.

Recently I've noticed that I'm maintaining a 5000 IP Profile even though my sync is sometimes just below what's widely documented as the starting point sync of 5696 for a 5000 profile.

It would be good news if BT have made the threshold more 'generous' as it will help others in the same situation as me - i.e. close to the next profile increase.
I'm right on the limit today but I've still got a 5000 IP Profile.
Anyone else seeing threshold changes or if it just my lucky week

BT speedtester reports:
Your DSL Connection Rate :5664 Kbps(DOWN-STREAM), 448 Kbps(UP-STREAM)
IP Profile for your line is - 5000 Kbps

I had this for a week then they kicked the profile down to 1mb just for the hell of it

This happened to me a few times, got to the stage where my profile was above my sync rate and it was like having LLU. Only lasted a couple of weeks

In reply to a post by krazykizza:

...and it was like having LLU.

A dream!

I've read that people on ADSL2+ sometimes see some strange DLM behaviour but I'm only on plain old ADSL.

Syncing at 5728 today - I'll check my profile next time I see a sync in the lower 56xx
If it's a BT change then it's a good one! (is that an oxymoron?)