"Let's say Teck makes an offer and Copper Fox accept the offer. How long does it takes after that we can sell our shares for the offered price? Or when offered Teck shares, how long does it takes to receive them after CUU accepted the offer? Never been in this situation before so hope to learn more from you guys."

Normally the market will react fairly quickly and CUU's sp would adjust to close to the offer price. You can sell the CUU shares and make most of the final offer price.

If you want to wait, the offer has to go thru the Board. Once the Board has reviewed the offer and recommended it to the shareholders, shareholders can tender their shares through their brokers for cash or for Teck shares. You may have to wait until a certain minimum % has been tendered; but in this case it can be fairly swift because insiders hold a big chunk. JMO

Sorry to be redundant; I see a couple of quick fingers are ahead of my reply!