Yes this will be a scam!
070 numbers are like 08xx numbers in so much as they need to be pointed (diverted) to 'normal' numbers. The Ofcom rules used to say that the receiver can be paid revenue (like with 084/087). As they can cost upto 50p/min from a BT landline, they are therefore worse than 0870 and may therefore be viewed as premium rate. The cost of the call gives you an idea of what sort of revenue the receiver will get.
Ofcom has now stopped the receiver benefiting. Instead, an intermediate party can receive revenue on the call, rather than the end subscriber. So what do you think happens, yes the end subscriber puts themselves down as the intermediate party and puts a "dummy" subscriber down as the end subscriber.
Ofcom's numbering lists show that the prefix 070617 is allocated to
Hotchilli Communications.