I have a better idea. Don't deposit to coinbase!
There are still exchanges that don't make you wait 2 weeks. This is really ridiculous. They could require more confirmations than usually like increase the number 3 times. 2 weeks is something only coinbase could think of.
It's on ETC side which has a problem. Because of the recent network attacks. A lot of exchanges are prolonging withdrawal/depositing in order to prevent any problems. Well if you want to deposit in a garbage exchange and have problems later, sure.
You can have more context here and here if you want to read it.
So you must think coinbase is not a garbage exchange?
You don't need a 2 week delay to know if there was a 51% attack or not. They are overdoing it.
I'm not saying ETC isn't a shitcoin, but Armstrong isn't a saint either.
You can find a lot of interesting reads in the web https://en.ethereumworldnews.com/coinbase-hiles-fee-233-pro-site-outrage-traders/