I'm experiencing the opposite!
I signed up on Tuesday, and on Wednesday they dropped the monthly by a fiver and increased the reward card by £25!
Called them up in the morning to cancel (and reorder later/following day) but the chap I was speaking to agreed to drop my package price by £7 to account for the drop in monthly and increase in reward card.
Tuesday, £34.99/12m and £125 reward card
Wednesday £29.99/12m and £150 reward card
So dropping my monthly to £27.99 brings it very close, and shouldn't effect my quidco, in theory.
Let's not mention that quidco cashback has now since increased from £80 to £110...!