My current bonus is ~5 months, the new bank also indicate their bonus is 4-5 months subject to the usual performance criteria. So annual package works out to be a slight increase.

Anyway I went back to the recruiter to renegotiate and she managed to get a 5.3k offer which I accepted verbally and will be going down to sign once they complete all the checks and prepare the letter.

Thanks to all for your feedback.