Could be, or could be the the PR update is in progress. I've get the same results for my site and yesterday it predicted PR4 with 254 backlinks. Today it says Insufficient backlinks
iWebtools have had issues with all there tools for months now, they are also not very accurate (although pr prediction tools never are unfortunately...)
Thank you for the kind offer. I have added 2 sites to your computer and internet section. Kindly awaiting approval