Thanks for that. I suppose I achieved the underlay by treating the £45 as SNR when calculating the lay stake. So far so good. What I still don't get is this:
As things stand, I'll be £25 in profit if I win at the exchange and that's the end of it. But if I win at the bookie's I'll still be £25 up and
I'll still have the £45 bonus. So, if I repeat exactly the same process - place another bet of £145 and count the bonus amount as SNR when calculating the lay stake - aren't I going to continue making a profit as well as keeping the bonus until I lose at the bookie's (in which case, any further bets are completely SR)?
Maybe some numbers might help:
£100 + £45 back at 3.35 - return = £485.75 (net 340.75)
£131.57 lay at 3.4 - liability = £315.76
Bust out, and I have my original £100 + £24.99 (after commission)
Win at bookie and I have 485.75 - 315.76 = 169.99 = £100 + £45 + 24.99
By treating the bonus as SR and going for higher odds (which I can't really do just yet anyway), I would bust out with a greater profit but win at the bookie's with a lot less. On the other hand, completing the WR at lower odds and SNRing the bonus could make a profit of around £100 plus the now cashable bonus if I don't bust out at all.
Or is that considered gambling?
Or have I missed something blindingly obvious?