Over £16,000 savings limit due to PIP award

Hi.
I am currently on income related ESA (support group).
Was recently awarded PIP Standard Daily Living and Standard Mobility at Tribunal
after 19 month wait. This has meant £5,000 backdated payment of PIP, plus £5,000 backdated payment of ESA severe disability premium (which I'm now entitled to as a result of the PIP award). My savings were £8,000 at the time of the 2 backpayments, which have pushed me over the £16,000 savings limit.
I have just received my annual ESA letter asking me to detail any savings and property.
Will I be penalised by the DWP, even though it is their actions which have caused this situation?
Hope you can help.
J Brown

Thanks for your prompt reply! Very helpful.
The long process to getting the successful PIP award was made easier by the guides and forum information provided by your good selves at this website.
Thanks again.
J Brown

One query from your post, by subparagraph 11(2) and (3) Schedule 9 of the ESA regulations 2008, arrears of income related benefit over £5000 awarded during the currency of an income related award is disregarded for the duration of that award. My conclusion is that the arrears of income related benefit over £5000 should be disregarded beyond the 52 week period if there is no break in the income related claim. The regulation is long-winded and obscure and PIP is not income related but is disregarded as income. Most guidance skirts the point. I am hoping I'm right for the claimant's sake.