Who did really think they could stick to their timeline? It's a huge project and the first one of its kind. It was pretty clear they would need more time than expected. I wouldn't even be surprised if they would announce a second delay in a few month.
Nevertheless I hope rewriting the whole code was the right decision.
Very true. As I knew very well that 95% of all mega projects(be it programming or non-programming) were subjected to delay in common, I already spared a six months delay for Wagerr the very first time I read the roadmap during ICO. Therefore this one doesn't hurt my sentiment at all.
Oppositely, by staying closely and observing every word the team frequently spoke on slack, I'm absolutely sure that this delay is a total positivity for the long run. Firstly, it has minimized the possible delay for mainnet as expected bugs and other programming hassles can be solved easier during this period before the official release. Secondly, launching the blockchain on 15th Jan doesn't effect the timeline much. But it would have avoided many technical failures causing price dips after the launch. Thirdly, I myself don't like to mess too much time with the experimental testnet, to avoid being implicated by the technical problems which were supposed to be solved at the dev's own obligation before exposing it to the public.
They have clarified on Wagerr Slack that they are not necessarily to rewrite the code. But they must revamp and improve it to strengthen the security and workability.