I am working as a temp to hire (I have an employer but work for someone else). I was given a salary range by the temp agency of what my salary would be when I was hired the company whose work I do.

Recently I spoke with local management, who gave me a different range that overlapped only slightly with the first range and is approximately 15% lower. They informally offered a wage at the very bottom of the initial range and near the top of the more recent range. It feels like I'm being low-balled and simultaneously manipulated.

Since I cannot be hired for two months, how should this affect my negotiation?