The historic halls of the London Stock Exchange (LSE) are about to get a digital upgrade. Get ready for Bitcoin and Ether exchange-traded notes (ETNs) to start trading on May 28th, marking a significant step for cryptocurrencies in the U.K.

This news comes after the Financial Conduct Authority (FCA) gave the green light in March, allowing the LSE to list these crypto-backed products specifically for professional investors.

Think of these ETNs as investment vehicles that track the price of Bitcoin and Ether, similar to how stocks track companies. But with a twist: these ETNs are physically backed by the actual cryptocurrencies, stored securely in cold storage.

The LSE is opening its doors for applications starting April 8th, but don't dawdle – issuers have until April 15th to submit their proposals, including a detailed plan for FCA approval.

This move by the LSE positions London as a potential hub for institutional crypto investment. However, a shadow hangs over the celebration. Industry experts are criticizing the FCA's decision to restrict these ETNs to "professional investors" only. This means everyday investors won't be able to participate in this new market segment.

The FCA argues that the volatile nature of crypto makes these ETNs risky for retail investors. But some, like Bradley Duke of ETC Group, remain hopeful that the ban will be lifted in the future. "The LSE is a crucial market for us," he said, "and we're prepared to list products as soon as possible."

Will the U.K. follow the lead of other countries and open the doors to retail investors? Only time will tell. But one thing's for sure: the chimes of Big Ben are about to be joined by the hum of the blockchain revolution.