Peterborough's not even particularly deprived.
If you have a look at, for example, the Indices of Deprivation 2015 or the Index of Multiple Deprivation you'll see that there are quite a few areas within Peterborough that are in the top 10% most deprived areas in the country.
However, there are equally areas of Peterborough that are very different.
So, it's fair to say that Peterborough, as a whole, isn't particularly deprived but there are some parts of it that really do rank in some of the very most deprived areas of the country.
It's not classic UKIP territory.
True, they only ever had four seats on the local council and tied in third place with the Lib Dems. Nowadays they have no seats at all.
BXP seems to have wider appeal.
I would agree with you. As UKIP moved to an increasingly right wing position I think a lot of people wouldn't touch them with a barge pole.
Also, there are issues specific to Peterborough that a large number of people consider are being made worse by remaining in the EU. Yes these issues are issues that the government should sort out but it is also true that many people believe that the situation is being exacerbated by remaining in the EU and, as the old saying goes, if you're in a hole then stop digging.