At no point feel a hostage of previous comms or even your choices. It’s bad for both parties if you join in bad spirit. It’ll be appreciated if you get a face-time with recruiter or hiring manager and explain calmly that your situation at current place has changed since the first conversation, both financially and in scope of impact. Then construct your argument depending on if you’d like to raise and leave (explain that you are really keen to join but these are the challenges/impact/income that will be leaving behind if join) or to stay (valued, getting new challenges etc - exactly what you were looking for when applying). It’s very common that people are retained after accepting offer elsewhere, and companies always bear this risk in mind. As long as you stay professional and transparent, i do not see why it should backfire. You are doing yourself and the a favour of avoiding a disheartened hire.

Thanks for a great advice. I definitely felt that way. I’ve now taken a big risk to ask for a zoom meeting with the head of this role. Even though my joining is just 2 days away. I’m going via the recruiter and not bypassing her and not even trying to reach via the peoples team. To add to the complexity I was offered the same role via the same referral in 2022 when I chose my current employer. It can definitely go more on the negative side now. But I feel I’ve been offered a 2 year old package which isn’t fair on my work experience and gain in skills in the past 2 years. Fingers crossed let’s see how it goes. Recruiter was pissed off during our last conversation but I’ve tried to explain my best through an email and asked for a fair chance to speak with the head.