Upvote:3
If you have ILR, it is vital that you do not enter the UK as a tourist, since that can lead to loss of your ILR. From VisaLogic:
There are a number of circumstances that may cause you to lose your Indefinite Leave To Remain status. For example, if you leave the UK and upon return are granted leave to enter the UK other than for an indefinite period.
If you turn up at the border you might be let through as a resident without your BRP, but if the border agent mistakenly clears you as a tourist then you will accountable for the mistake (not them!) If you don't have ILR, it seems it won't lead to your visa being cancelled but it's likely to cause problems later down the line, e.g. when you apply for IRL. Also, don't overstay as a tourist because that will affect your chances at future visa applications.