Checking Building Contract

After almost 3 months, we haven't started yet, mainly because we lost 1 month to Christmas/New Year, then about 1 month to relocate the underground rainwatertank, then all those tiles/carpet drama, then now waiting for the final sign off.

I've been checking today of my building contract, it said :

Commencing the Building Works

- The builder is to commence the building works within 20 working days after the day that :

a. The builder receives all necessary building permits 7 planning approvals for the building works to commence

b. The owner satisfies all of the requirements of clause 4.

Well, I have got my CC and everything's else last month, so they should start the excavation soon...