No not witdrawals. Is there a Coinbase imposed limit to how many Bitcoins I can send to another wallet? And was that recently implemented?

Coinbase certainly has conversion limits, but anyone that wanted their Bitcoin into Dollars knew about this limit far before the warning of Coinbase only supporting one side of the split, and converting into Dollars means you don't want to risk the split and you should have been diversifying far before Coinbases announcement.