The sudden increase of ETH price is possibly because of Spedn, an ethereum based apps that accept several cryptocurrency.
The app works with Bitcoin, Ethereum, Bitcoin Cash, and Gemini currencies. Spedn generates a barcode that the cashier can scan. Retailers do not need any new hardware to accept the payment method. They only need to configure their scanners to read the Spedn codes.
https://www.techspot.com/news/80072-flexa-spedn-app-you-pay-crypto-several-retailers.htmlIt also affect Eth the same way it affected BTC. As for the decline in price of Bitcoin, I believe in every major run there is always a set back for correction which we are now seeing. This is normal.
I also agree that there is no Flippening because both cryptocurrency reacted positively on the news about starbucks and other stores accepting cryptocurrency.
Just wanted to give my opinion about this matter, BTC and ETH are not meant to be for the same purpose to start with, one is meant to build applications on and the other is a digital cash system.
Most traders does not give a thing about the usage of each cryptocurrency. They are here to profit so if they see even a little window to get a profit in a trade, they will grab it regardless of what they are trading.